Re: thermoquad VS. Holley 750 DP
[Re: babarracuda]
#1031706
07/13/11 12:57 PM
07/13/11 12:57 PM
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Joined: Jan 2003
Posts: 3,719 Space Station #5
471Magnum
master
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master
Joined: Jan 2003
Posts: 3,719
Space Station #5
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TQ is going to give you way better mileage around town.
Throttle response will depend on a lot of factors. A DP can mask a lot of problems by just literally dumping fuel on it.
Performance and driveability can be great with a TQ, but they are a bit of a pain to tune. Bend this, straighten that. They were designed to be somewhat tamper resistant, so you can't just turn a screw here or there. Definitely need to do your homework.
I've always considered myself to be a Holley guy, but I'm currently working through my first TQ tuning experience and learning as I go.
-Jim
I can fix it... my old man is a television repairman. He's got the ultimate set of tools... I can fix it.
Currently Mopar-less
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Re: thermoquad VS. Holley 750 DP
[Re: Spanky]
#1031716
07/13/11 03:55 PM
07/13/11 03:55 PM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Smaller primaries will do better on gas then the larger, its not rocket sience, thats "only" if both carbs are tuned properly at the exact same AFR, if the 750dp is tuned lean on the primaries & the TQ is rich then yeah, the 750dp will most likely do better, Your demand is less on a smaller primary carb, the jets are smaller, less fuel, less air, better mileage, the intake also plays a role in it too, so does the cam. Its easy to figure out really, all your engine is is a vacuum pump that runs off combustion, it pulls in air/fuel & lets it out, if you restrict it, it'll consume less, a larger CI engine will demand more, thus consume more, Your engine will only pull what it needs, but on the other hand it "can" be controlled as to how much you want to give it.
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Re: thermoquad VS. Holley 750 DP
[Re: joedust451]
#1031717
07/13/11 05:56 PM
07/13/11 05:56 PM
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Joined: Jan 2003
Posts: 3,719 Space Station #5
471Magnum
master
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master
Joined: Jan 2003
Posts: 3,719
Space Station #5
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The double pumper has the ability to give a massive pump shot in all four venturies as all four open in light throttle situations, which is great for big cams and heads with low port velocity and "city" type rpms. Great for getting a car out of the hole quickly, but lousy on fuel mileage.
In a steady state cruising situations, both could be tuned for equal fuel economy. Steady state is not what you're dealing with in around town. The dinky high velocity primaries are what is what makes the thermoquad inherently better and delivering fuel economy around town.
Likewise, both are capable of being absolute turds if they aren't tuned properly.
-Jim
I can fix it... my old man is a television repairman. He's got the ultimate set of tools... I can fix it.
Currently Mopar-less
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Re: thermoquad VS. Holley 750 DP
[Re: 471Magnum]
#1031719
07/13/11 09:05 PM
07/13/11 09:05 PM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Quote:
The double pumper has the ability to give a massive pump shot in all four venturies as all four open in light throttle situations,
Where did you come up with this theory , "light throttle" situations, try more like "half throttle", unless your useing one of these holleys or any with 1.1 linkage.
http://www.jegs.com/i/Holley/510/0-4224/10002/-1
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031723
07/14/11 01:22 AM
07/14/11 01:22 AM
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Joined: Feb 2003
Posts: 21,318 Manitoba, Canada
DaytonaTurbo
Too Many Posts
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Too Many Posts
Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
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Quote:
Quote:
The TQ or QJ will still win over a squarebore carb, smaller primary bores get better mileage if the AFR is the same on both carbs. & you can make a 750dp get right at the same mileage as a 3310.
if ther A/F ratio is the same for either carb, can you please explain why one will get better mileage over the other? same amount of air, same amount of fuel.
the one thing i could never get used to on a spread bore carb is how much further you need to push the gas pedal in normal driving to get the same acceleration as a square bore carb.
The smaller venturis are supposed to be more responsive to small changes in vacuum/load during normal driving, so they should respond more precisely to fine changes in throttle position as you would encounter during daily driving. FWIW I always found spread bore carbs to be more responsive when driving around town than square bore carbs.
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031724
07/14/11 01:33 AM
07/14/11 01:33 AM
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Joined: Jul 2008
Posts: 30,250 Florida STAYcation
dIc dOc Deity !
The village idiot's idiot
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The village idiot's idiot
Joined: Jul 2008
Posts: 30,250
Florida STAYcation
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Quote:
if ther A/F ratio is the same for either carb, can you please explain why one will get better mileage over the other? same amount of air, same amount of fuel.
BECAUSE the TQ does a BESTer job mixing air and fuel on the primary side than any other carb out there. Just-like EFI does a better job than any carb.
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Re: thermoquad VS. Holley 750 DP
[Re: DaytonaTurbo]
#1031726
07/14/11 08:10 AM
07/14/11 08:10 AM
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Joined: Jan 2003
Posts: 24,562 Brookeville, Md
Mr.Yuck
Not enough dumb comments...yet
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Not enough dumb comments...yet
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
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Quote:
Quote:
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The TQ or QJ will still win over a squarebore carb, smaller primary bores get better mileage if the AFR is the same on both carbs. & you can make a 750dp get right at the same mileage as a 3310.
if ther A/F ratio is the same for either carb, can you please explain why one will get better mileage over the other? same amount of air, same amount of fuel.
the one thing i could never get used to on a spread bore carb is how much further you need to push the gas pedal in normal driving to get the same acceleration as a square bore carb.
The smaller venturis are supposed to be more responsive to small changes in vacuum/load during normal driving, so they should respond more precisely to fine changes in throttle position as you would encounter during daily driving. FWIW I always found spread bore carbs to be more responsive when driving around town than square bore carbs.
just here but since the TQ has much smaller primarys wouldn't that make the secondarys open faster? As mentioned before by me and others, a tuned carb is going to use the fuel/air it needs to push the car. What about a 6-pack? It runs off a small 2bbl most of the time. Anybody got andy real world numbers?
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031727
07/14/11 09:53 AM
07/14/11 09:53 AM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Quote:
Quote:
The TQ or QJ will still win over a squarebore carb, smaller primary bores get better mileage if the AFR is the same on both carbs. & you can make a 750dp get right at the same mileage as a 3310.
if ther A/F ratio is the same for either carb, can you please explain why one will get better mileage over the other? same amount of air, same amount of fuel.
the one thing i could never get used to on a spread bore carb is how much further you need to push the gas pedal in normal driving to get the same acceleration as a square bore carb.
Its not really the same amount, i'm only talking on the primary side, Who drives around at WOT all the time, you have less air/fuel being drawn in on the smaller primary carb staying on the primaries, but yhou can still adjust the AFR to where you want it, now why wouldn't you think if the AFR was the same on both carbs, that the larger throttle bores would get the same mileage, The engine is able too pull in more air at the same throttle possition as the smaller primary carb,, lets say 1/4 on both carbs, so the larger throttle bodied carb lets the engine draw more air, more air needs more fuel, resalting in more consumption, its not a brain teaser.
But i do agree with you on how the larger primary carb feels better under moderate throttle (more responsive) then the smaller primary carb
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Re: thermoquad VS. Holley 750 DP
[Re: Mr.Yuck]
#1031729
07/14/11 11:13 AM
07/14/11 11:13 AM
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Joined: Nov 2004
Posts: 2,825 Sk. Canada
RemCharger
master
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master
Joined: Nov 2004
Posts: 2,825
Sk. Canada
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Quote:
Quote:
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The TQ or QJ will still win over a squarebore carb, smaller primary bores get better mileage if the AFR is the same on both carbs. & you can make a 750dp get right at the same mileage as a 3310.
if ther A/F ratio is the same for either carb, can you please explain why one will get better mileage over the other? same amount of air, same amount of fuel.
the one thing i could never get used to on a spread bore carb is how much further you need to push the gas pedal in normal driving to get the same acceleration as a square bore carb.
The smaller venturis are supposed to be more responsive to small changes in vacuum/load during normal driving, so they should respond more precisely to fine changes in throttle position as you would encounter during daily driving. FWIW I always found spread bore carbs to be more responsive when driving around town than square bore carbs.
just here but since the TQ has much smaller primarys wouldn't that make the secondarys open faster? As mentioned before by me and others, a tuned carb is going to use the fuel/air it needs to push the car. What about a 6-pack? It runs off a small 2bbl most of the time. Anybody got andy real world numbers?
I thought the center carb on a 6 pak was like a 500. Same as a 67 and down carter 4 bbl
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Re: thermoquad VS. Holley 750 DP
[Re: Rug_Trucker]
#1031737
07/14/11 01:44 PM
07/14/11 01:44 PM
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Joined: Jan 2003
Posts: 24,562 Brookeville, Md
Mr.Yuck
Not enough dumb comments...yet
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Not enough dumb comments...yet
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
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Quote:
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"TQ's are great if you fix the throttle shaft slop in the rebuild. Also buy an air door tool off of Doc.
My 511 '67 Cuda got 14mpg combined with the 6pak."
I noticed on the 1st 6-pack build (mild 440 w/ 528 solid) I was getting pretty good milage. This build is much more agressive and on the last trip to the track (22 miles) I avg'd about 13-14. Not bad considering I got on it a few times. This is mainly backroads (45mph) stopping in 4 small towns.
Read down lower in my post. I got 7mpg. 3:23's .538-.5?? Crane solid cam.
I'm running .030 over 440 w/ a 588 solid roller, ported stage VI heads, 3800 stall and 3.91's. I think my good milage was do to a nice slow steady drive of 40-45mph. Not much stop/start and not much outboard action...
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Re: thermoquad VS. Holley 750 DP
[Re: Paul_Fancsali]
#1031741
07/16/11 04:16 AM
07/16/11 04:16 AM
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Joined: Jul 2005
Posts: 384 Australia
Mcode69
enthusiast
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enthusiast
Joined: Jul 2005
Posts: 384
Australia
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Quote:
The TQ takes a lot to tune and is absolutly no comparison to a DP Holley. I tried to run a TQ and succeeded but in the end the Holley won out hands down in Performance. When you are talking tenth's of a second I will now stick with Holley. PS in mileage try a Q jet easy to tune and reliable and with Chrysler linkage from 1985 up to 1988
If the holley won hands down in performance it means your TQ was WAY out of tune. I've had a 750DP and a TQ on the same engine and the difference was 11 mpg from the holley and 17 from the TQ around town. Never saw any track times but the TQ had the holley by the butt dyno. And apart from that [and here's a name from the past] Ed Hamburger insisted that a TQ will have 2 tenths over a similar sized double pumper all day. As someone stated previously holley tend to cover up deficiencies in their design by making it rich, they CANNOT meter fuel properly at part throttle apart from all their other problems.
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Re: thermoquad VS. Holley 750 DP
[Re: Mr.Yuck]
#1031744
07/16/11 08:26 AM
07/16/11 08:26 AM
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Joined: Jun 2008
Posts: 10,847 Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,847
Oakdale CT
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Quote:
"TQ is going to give you way better mileage around town."
how's that? the engine is going to pull the needed fuel amount reguardless of carb.
Ever drive your car around with an O2 meter and a vacuum gauge?
Ran both a TQ and a Holley on my GTX, the Holley was atrocious when it came to transitions from circuit to circuit. Spent over a month trying to get the Holley to work as well as the TQ, it just could not do it due to the design.
Holleys really do cover flaws in their design with "more fuel" at least the one I was working on did.
For a race application I would not have a problem with either a TQ or Holley but for the street I'd run nothing but a TQ IMHO.
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Re: thermoquad VS. Holley 750 DP
[Re: Mcode69]
#1031745
07/16/11 10:21 AM
07/16/11 10:21 AM
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Joined: Jan 2003
Posts: 24,562 Brookeville, Md
Mr.Yuck
Not enough dumb comments...yet
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Not enough dumb comments...yet
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
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Quote:
Quote:
The TQ takes a lot to tune and is absolutly no comparison to a DP Holley. I tried to run a TQ and succeeded but in the end the Holley won out hands down in Performance. When you are talking tenth's of a second I will now stick with Holley. PS in mileage try a Q jet easy to tune and reliable and with Chrysler linkage from 1985 up to 1988
If the holley won hands down in performance it means your TQ was WAY out of tune. I've had a 750DP and a TQ on the same engine and the difference was 11 mpg from the holley and 17 from the TQ around town. Never saw any track times but the TQ had the holley by the butt dyno. And apart from that [and here's a name from the past] Ed Hamburger insisted that a TQ will have 2 tenths over a similar sized double pumper all day. As someone stated previously holley tend to cover up deficiencies in their design by making it rich, they CANNOT meter fuel properly at part throttle apart from all their other problems.
Then the holley was way out of tune. No way the TQ is going to get 6mpg better. And the TQ was probablt a 1050 vs a 750 at the track...
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Re: thermoquad VS. Holley 750 DP
[Re: Mr.Yuck]
#1031747
07/16/11 12:20 PM
07/16/11 12:20 PM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,275
Desert Tracker
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Quote:
I doubt you will see much differnce in MPG w/ a TQ. Unless your DP is way out of tune. Plus factor in you'll have to pay somebody to set it up then you have to figure how many miles you have to drive to make up any savings. Kind of like the fools that got rid of their paid for 20-22mpg cars to by a hybrid that gets 40's. How far would one need to drive to start saving money?
Mr. Y, at the strip, HOLLEYS are the NORM. Unless, you have a mild combo, in a LIGHT vehicle the DP suffers from some mileage penalty. And you need to run a SMALLER one (650) at that. WHO would want better mileage out of a mega-displacement motor anyway! The beauty of the TQ, is that besides it's generous airflow ratings, it's VERY tunable!! AND it can be bolted on (provided you have a TQ flanged intake) on ANY MOPAR motor (except the 6's, and as we speak someone will make manifolds for them TOO, eventually) and still perform WELL!! Great for the street and a SHOCKER on the STRIP!! Oh, did I forget to mention, it DOES get BETTER MILEAGE than the DP!! So does the 6 pack !!
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031749
07/16/11 02:31 PM
07/16/11 02:31 PM
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Joined: Jan 2003
Posts: 28,063 Irving, TX
feets
Senior Management
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Senior Management
Joined: Jan 2003
Posts: 28,063
Irving, TX
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It seems that many of you are forgetting that you don't drive on the street at exactly ONE throttle position.
Given one throttle position and one engine load you can make any carb perform great. Now, when you get into the on/off throttle application, hills, different engine loads due to added weight in the vehicle, and the billions of other real world situations the design of the TQ will be able to give you better economy than a Holley DP. Think about that Holley for a second. Move the throttle and it opens primary and secondary bores with both accelerator pumps dumping fuel. The TQ opens the primaries and if the draw is strong enough it will begin opening the secondaries and back off as the load is eased. The pump will shoot fuel but not to the degree of the Holley.
On a drag strip or race car the Holley will be hard to beat. The TQ could hold it's own but that would require an expert's touch.
When I was playing with carbs I could normally get the best performance (butt dyno) out of a Holley. However, once tuned to performance the Holley was way behind the AFB and TQ when it came to street manners. Since my cars are street cars I did not run Holley carbs for long.
We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind. - Stu Harmon
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Re: thermoquad VS. Holley 750 DP
[Re: goldmember]
#1031751
07/16/11 03:34 PM
07/16/11 03:34 PM
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Joined: Sep 2003
Posts: 1,465 Carson City, NV
babarracuda
OP
pro stock
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OP
pro stock
Joined: Sep 2003
Posts: 1,465
Carson City, NV
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I know several guys with TQ on their 360's that run SS. None of these guys thinks a 750DP will perform like a TQ. I realy don't care if a DP is faster at the races, I want to drive to see my cousin and old racing buddies at Famoso, San Luis Obispo and Simi Valley, CA. Some of the rants must be made without the brain in gear. A 1 3/8 primary VS. a 1 11/16 cannot pass the same amount of fuel. A small hole has better velosity than a large hole. These are not my ideas, just scientific facts. Why doesn't a Holley DP get the same mileage as an Edelbrock 750. Could it be metering rods instead of power valve? If you read my first post, I said I was going to have the carb setup, not screw it up with my lack of Thermoquad knowledge. A friends omnce toild me that the really smart man doesn't know everything, he just knows where to get HELP!!!
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Re: thermoquad VS. Holley 750 DP
[Re: feets]
#1031752
07/16/11 03:36 PM
07/16/11 03:36 PM
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Joined: Jan 2003
Posts: 9,826 las vegas
70AARcuda
master
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master
Joined: Jan 2003
Posts: 9,826
las vegas
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[quoteThink about that Holley for a second. Move the throttle and it opens primary and secondary bores with both accelerator pumps dumping fuel. The TQ opens the primaries and if the draw is strong enough it will begin opening the secondaries and back off as the load is eased. The pump will shoot fuel but not to the degree of the Holley. When I was playing with carbs I could normally get the best performance (butt dyno) out of a Holley. However, once tuned to performance the Holley was way behind the AFB and TQ when it came to street manners. Since my cars are street cars I did not run Holley carbs for long.
Not true on a holley dp...the secondary throttle blades and acelerator pump do not begin to open until the primaries open 40 degrees...
Tony
70 AARCuda Vitamin C 71 Dart Swinger 360 10.318 @ 128.22(10-04-14 Bakersfield) 71 Demon 360 10.666 @122.41 (01-29-17 @ Las Vegas) 71 Duster 408 (10.29 @ 127.86 3/16/19 Las Vegas)
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Re: thermoquad VS. Holley 750 DP
[Re: feets]
#1031757
07/16/11 09:30 PM
07/16/11 09:30 PM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Quote:
The TQ opens the primaries and if the draw is strong enough it will begin opening the secondaries and back off as the load is eased. The pump will shoot fuel but not to the degree of the Holley.
Not true, The secondaries will not start (be able) to open untill at least 40% throttle. Same with a QJ.
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031761
07/17/11 02:37 AM
07/17/11 02:37 AM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Quote:
Quote:
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The TQ opens the primaries and if the draw is strong enough it will begin opening the secondaries and back off as the load is eased. The pump will shoot fuel but not to the degree of the Holley.
Not true, The secondaries will not start (be able) to open untill at least 40% throttle. Same with a QJ.
To a point. The air door IS adjustable! When you have smaller, efficient, double venturi primaries working for you, there is a LOT of high velocity AIRFLOW going into the motor, more so than a Holley. Makes for a BETTER burn in the cylinders. The bigger secondary bores provide additional air/fuel flow to the already higher velocity primary jet stream. More torque!!
Not talking about the air door, alot of what your saying has nothing to do with what i said , not trying too be a jerk, just saying.
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Re: thermoquad VS. Holley 750 DP
[Re: joedust451]
#1031762
07/17/11 02:58 AM
07/17/11 02:58 AM
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Joined: Jul 2010
Posts: 2,091 Delray beach, Florida
Performance Only
top fuel
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top fuel
Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
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if the thermoquad is really so much better than a holley carb in fuel economy for the daily driver and also performance on the track, what would the reason be that so many people prefer something other than a thermoquad? surely there must be a reason that 99% of people choose something else isn't there? can that many people be wrong?
machine shop owner and engine builder
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031763
07/17/11 03:22 AM
07/17/11 03:22 AM
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Joined: Apr 2011
Posts: 450 owensboro, ky
rallye73
mopar
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mopar
Joined: Apr 2011
Posts: 450
owensboro, ky
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Quote:
if the thermoquad is really so much better than a holley carb in fuel economy for the daily driver and also performance on the track, what would the reason be that so many people prefer something other than a thermoquad? surely there must be a reason that 99% of people choose something else isn't there? can that many people be wrong?
Probably the same reason why Chevy guys think a small belongs in everything...because it is all they know. Most people don't wanna take the time to set the carb up right. So when it doesn't perform the way they thought it would they just ditch it for the Holley. Same with the QJ. People complain about the bog in those too, but you can tune it out of them also. Only thing with the QJ is they never made as large of a cfm as the thermoquad. 800 was the biggest they had.
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031767
07/17/11 08:10 AM
07/17/11 08:10 AM
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Joined: Jan 2003
Posts: 6,389 nielsville, minn.
quickd100
master
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master
Joined: Jan 2003
Posts: 6,389
nielsville, minn.
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Thermoquad, Holley, they're both fuel delivery devices. Both have their good points and falts. They both can be set up to scream or fall on their faces. Holleys main advantage is numbers, there are more of them, and way more aftermarket parts available for them. The Thermoquad was the high water mark for Carter, one Rochester engineer once said the Thermoquad was the next step in development after the quadrajet. I have Holleys sitting on the shelf from 600cfm units all the way up to 1140cfm and I use them too. I really like the Thermoquad, they're CHEAP, give good mileage, and make great power, and are easy to modify. I can take a 850 thermoquad and modify it and it will run great on a 318 to a stroker Hemi. One day when I get caught up I'll do some back to back dyno tests with a Thermoquad vs. Holleys. Dave
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Re: thermoquad VS. Holley 750 DP
[Re: Mcode69]
#1031768
07/17/11 09:47 AM
07/17/11 09:47 AM
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Joined: Jul 2010
Posts: 2,091 Delray beach, Florida
Performance Only
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top fuel
Joined: Jul 2010
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Delray beach, Florida
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Quote:
It's the same reason most morons are into chevs, they just don't know any better! And apart form all this what about all the other problems holleys have, the stripped out threads, the baseplates that are made out of cheese, the fact that the basic design with all the leaks and all the other problems is out of the 50's, the fact that in warm weather they wont start when hot because they boiled over when you turned the engine off, this is a classic, holley couldn't fix it so they gave it a name... "flash boil" the fact that a tiny spec of dirt gets in them and they go haywire. I could go on and on if you guys are happy with junk so be it!
so i guess what should be taken from this thread is what? most morons like chevies and only a select few people in the world know how to tune a thermoquad? i've been playing with cars since the 1960's and as i recall, by then the holley 4150's and 4160's had been out for quite some time. the TQ didn't arrive until around 1969. during the years to follow i don't recall many (if any) people touting the TQ as the greatest carb on earth like i see in this thread today. i wonder why that is? to think no one could ever tune one properly would be a ludicrous thought. the argument that they just weren't as popular without an explanation is just crazy talk. if the argument is that they didn't make as many carbs as holley did, well, that's true, but why? if they were the latest and greatest, Carter surely would have made more. right? they must have some inherent drawback that caused their demise. not only did Chrysler Corporation give up on them, but also the performance crowd of the 70's and 80's etc. so now you'd have one believe that they really are all that and a bag of chips 40+ years later. hasn't history taught us this lesson already? i've owned a few thermoquads over the years and they performed as well as one could expect. okay mileage, no bogs, etc etc. the fact is none of them ever performed as well as a comparable sized 4150 holley. i never cared for the fact that the primary's are so small that you'd have to put the pedal half way to the floor to get the same acceleration as a 4150 does at less than 1/4 throttle. i never cared for that quadrajet sound of the secondary's opening. some thought it sounded cool, although i didn't. it was mostly noise to me. every car i ever had with a thermoquad eventually got replaced with a holley. the cars drove better and were always faster at the race track. perhaps those are just some of the reasons the thermoquads went the way of the dinosaur. oh, and by the way, don't tell me about holleys that have stripped bolt holes or leaks. we all know what caused the threads to strip out. maybe we can talk about cracked and leaking phenolic carb bodies instead, or some of the other inherent design flaws of the lately much revered thermoquad, or maybe you'd rather not...
machine shop owner and engine builder
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031769
07/17/11 10:20 AM
07/17/11 10:20 AM
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Joined: Mar 2005
Posts: 2,172 Ohio
theclutcher
top fuel
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top fuel
Joined: Mar 2005
Posts: 2,172
Ohio
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Why not have the best of both worlds. The spreadbore Holley 6210. Now everyone can be happy, not to mention it is a great carb... dbl pumper with 50 cc on secondary, tuneable with small primary.
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031771
07/17/11 01:15 PM
07/17/11 01:15 PM
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Joined: Jan 2003
Posts: 28,063 Irving, TX
feets
Senior Management
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Senior Management
Joined: Jan 2003
Posts: 28,063
Irving, TX
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Why didn't the factory engineers put the Holley 750 DP on high performance engines. It was readily available at the time.
We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind. - Stu Harmon
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031772
07/17/11 01:34 PM
07/17/11 01:34 PM
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Joined: Jan 2005
Posts: 12,406 Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,406
Kalispell Mt.
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Quote:
Quote:
It's the same reason most morons are into chevs, they just don't know any better! And apart form all this what about all the other problems holleys have, the stripped out threads, the baseplates that are made out of cheese, the fact that the basic design with all the leaks and all the other problems is out of the 50's, the fact that in warm weather they wont start when hot because they boiled over when you turned the engine off, this is a classic, holley couldn't fix it so they gave it a name... "flash boil" the fact that a tiny spec of dirt gets in them and they go haywire. I could go on and on if you guys are happy with junk so be it!
so i guess what should be taken from this thread is what? most morons like chevies and only a select few people in the world know how to tune a thermoquad? i've been playing with cars since the 1960's and as i recall, by then the holley 4150's and 4160's had been out for quite some time. the TQ didn't arrive until around 1969. during the years to follow i don't recall many (if any) people touting the TQ as the greatest carb on earth like i see in this thread today. i wonder why that is? to think no one could ever tune one properly would be a ludicrous thought. the argument that they just weren't as popular without an explanation is just crazy talk. if the argument is that they didn't make as many carbs as holley did, well, that's true, but why? if they were the latest and greatest, Carter surely would have made more. right? they must have some inherent drawback that caused their demise. not only did Chrysler Corporation give up on them, but also the performance crowd of the 70's and 80's etc. so now you'd have one believe that they really are all that and a bag of chips 40+ years later. hasn't history taught us this lesson already? i've owned a few thermoquads over the years and they performed as well as one could expect. okay mileage, no bogs, etc etc. the fact is none of them ever performed as well as a comparable sized 4150 holley. i never cared for the fact that the primary's are so small that you'd have to put the pedal half way to the floor to get the same acceleration as a 4150 does at less than 1/4 throttle. i never cared for that quadrajet sound of the secondary's opening. some thought it sounded cool, although i didn't. it was mostly noise to me. every car i ever had with a thermoquad eventually got replaced with a holley. the cars drove better and were always faster at the race track. perhaps those are just some of the reasons the thermoquads went the way of the dinosaur. oh, and by the way, don't tell me about holleys that have stripped bolt holes or leaks. we all know what caused the threads to strip out. maybe we can talk about cracked and leaking phenolic carb bodies instead, or some of the other inherent design flaws of the lately much revered thermoquad, or maybe you'd rather not...
The TQ was only canned by chrysler because carter went out of buisness due to poor managment, the q-jet filled in for a year and then EFI came out and no more carbs. When the TQ came out it replaced all the holleys, mabey the holleys were so good they just had to replace it with a worse carb When I raced my 66 dart I tried a bunch of different holley carbs and holley style carbs and none had a performance advantage over a t-quad but they all sucked more gas (BTW a 770 street avenger was the closest MPG and ran the same 1/8th mile times) I wish Holley would make an anular booster all aluminum version of the 770 street avenger, it would probably be able to get similar MPG and the only time you would waste fuel is when you change jets. Any one with 1/2 a brain can look down the throat of a carb and see witch one atomizes the fuel better and the TQ does a much better job and that is the real reason they get better MPG, like was mentioned holley covers up the bad transitions by dumping in more fuel. The reason no one ran TQs back in the day is they were convinced it was an emmision piece of junk, same reason no one liked 360s or 400s, no matter how good it was people think it is an emmision only item in spite of the fact they have more potential than the predasessor .
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: thermoquad VS. Holley 750 DP
[Re: feets]
#1031773
07/17/11 01:40 PM
07/17/11 01:40 PM
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Joined: Jan 2003
Posts: 24,562 Brookeville, Md
Mr.Yuck
Not enough dumb comments...yet
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Not enough dumb comments...yet
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
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Quote:
Why didn't the factory engineers put the Holley 750 DP on high performance engines. It was readily available at the time.
because it was more expensive????? I never said that MPG's wouldn't be better w/ a TQ, however if he has a DP now and it's running well. why muck w/ it? He'll have to BUY a TQ either pay somebody to set it up, or tune it himself and I doubt he'd get more tha 1 maybe 2 mpg's around town better.
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031774
07/17/11 01:43 PM
07/17/11 01:43 PM
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Joined: Sep 2004
Posts: 6,906 IL, Aurora
ademon
master
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master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
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Quote:
Quote:
It's the same reason most morons are into chevs, they just don't know any better! And apart form all this what about all the other problems holleys have, the stripped out threads, the baseplates that are made out of cheese, the fact that the basic design with all the leaks and all the other problems is out of the 50's, the fact that in warm weather they wont start when hot because they boiled over when you turned the engine off, this is a classic, holley couldn't fix it so they gave it a name... "flash boil" the fact that a tiny spec of dirt gets in them and they go haywire. I could go on and on if you guys are happy with junk so be it!
so i guess what should be taken from this thread is what? most morons like chevies and only a select few people in the world know how to tune a thermoquad? i've been playing with cars since the 1960's and as i recall, by then the holley 4150's and 4160's had been out for quite some time. the TQ didn't arrive until around 1969. during the years to follow i don't recall many (if any) people touting the TQ as the greatest carb on earth like i see in this thread today. i wonder why that is? to think no one could ever tune one properly would be a ludicrous thought. the argument that they just weren't as popular without an explanation is just crazy talk. if the argument is that they didn't make as many carbs as holley did, well, that's true, but why? if they were the latest and greatest, Carter surely would have made more. right? they must have some inherent drawback that caused their demise. not only did Chrysler Corporation give up on them, but also the performance crowd of the 70's and 80's etc. so now you'd have one believe that they really are all that and a bag of chips 40+ years later. hasn't history taught us this lesson already? i've owned a few thermoquads over the years and they performed as well as one could expect. okay mileage, no bogs, etc etc. the fact is none of them ever performed as well as a comparable sized 4150 holley. i never cared for the fact that the primary's are so small that you'd have to put the pedal half way to the floor to get the same acceleration as a 4150 does at less than 1/4 throttle. i never cared for that quadrajet sound of the secondary's opening. some thought it sounded cool, although i didn't. it was mostly noise to me. every car i ever had with a thermoquad eventually got replaced with a holley. the cars drove better and were always faster at the race track. perhaps those are just some of the reasons the thermoquads went the way of the dinosaur. oh, and by the way, don't tell me about holleys that have stripped bolt holes or leaks. we all know what caused the threads to strip out. maybe we can talk about cracked and leaking phenolic carb bodies instead, or some of the other inherent design flaws of the lately much revered thermoquad, or maybe you'd rather not...
I dont think many auto makers were using Holleys on much after 1971 or even before that, Carter was always on most GM and Mopars, they needed something that would hold the correct A/F ratio, so in came the QJ and TQ until throttle body injection. Also your statement about Chysler giving up on the thermoquad makes no sense, did they go to bolting up 800/850 Holleys in the mid 80's??? When it comes down to it the QJ and TQ are coming back into favor due to there flexibility and also some guys like to be different. Holley will always be on the majority of hot rods but its more interesting to see a the QJ/TQ getting it done
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Re: thermoquad VS. Holley 750 DP
[Re: HotRodDave]
#1031775
07/17/11 01:57 PM
07/17/11 01:57 PM
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Joined: Mar 2008
Posts: 571 Western NC
68Bullit
mopar
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mopar
Joined: Mar 2008
Posts: 571
Western NC
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Quote:
Quote:
Quote:
It's the same reason most morons are into chevs, they just don't know any better! And apart form all this what about all the other problems holleys have, the stripped out threads, the baseplates that are made out of cheese, the fact that the basic design with all the leaks and all the other problems is out of the 50's, the fact that in warm weather they wont start when hot because they boiled over when you turned the engine off, this is a classic, holley couldn't fix it so they gave it a name... "flash boil" the fact that a tiny spec of dirt gets in them and they go haywire. I could go on and on if you guys are happy with junk so be it!
so i guess what should be taken from this thread is what? most morons like chevies and only a select few people in the world know how to tune a thermoquad? i've been playing with cars since the 1960's and as i recall, by then the holley 4150's and 4160's had been out for quite some time. the TQ didn't arrive until around 1969. during the years to follow i don't recall many (if any) people touting the TQ as the greatest carb on earth like i see in this thread today. i wonder why that is? to think no one could ever tune one properly would be a ludicrous thought. the argument that they just weren't as popular without an explanation is just crazy talk. if the argument is that they didn't make as many carbs as holley did, well, that's true, but why? if they were the latest and greatest, Carter surely would have made more. right? they must have some inherent drawback that caused their demise. not only did Chrysler Corporation give up on them, but also the performance crowd of the 70's and 80's etc. so now you'd have one believe that they really are all that and a bag of chips 40+ years later. hasn't history taught us this lesson already? i've owned a few thermoquads over the years and they performed as well as one could expect. okay mileage, no bogs, etc etc. the fact is none of them ever performed as well as a comparable sized 4150 holley. i never cared for the fact that the primary's are so small that you'd have to put the pedal half way to the floor to get the same acceleration as a 4150 does at less than 1/4 throttle. i never cared for that quadrajet sound of the secondary's opening. some thought it sounded cool, although i didn't. it was mostly noise to me. every car i ever had with a thermoquad eventually got replaced with a holley. the cars drove better and were always faster at the race track. perhaps those are just some of the reasons the thermoquads went the way of the dinosaur. oh, and by the way, don't tell me about holleys that have stripped bolt holes or leaks. we all know what caused the threads to strip out. maybe we can talk about cracked and leaking phenolic carb bodies instead, or some of the other inherent design flaws of the lately much revered thermoquad, or maybe you'd rather not...
The TQ was only canned by chrysler because carter went out of buisness due to poor managment, the q-jet filled in for a year and then EFI came out and no more carbs. When the TQ came out it replaced all the holleys, mabey the holleys were so good they just had to replace it with a worse carb When I raced my 66 dart I tried a bunch of different holley carbs and holley style carbs and none had a performance advantage over a t-quad but they all sucked more gas (BTW a 770 street avenger was the closest MPG and ran the same 1/8th mile times) I wish Holley would make an anular booster all aluminum version of the 770 street avenger, it would probably be able to get similar MPG and the only time you would waste fuel is when you change jets. Any one with 1/2 a brain can look down the throat of a carb and see witch one atomizes the fuel better and the TQ does a much better job and that is the real reason they get better MPG, like was mentioned holley covers up the bad transitions by dumping in more fuel. The reason no one ran TQs back in the day is they were convinced it was an emmision piece of junk, same reason no one liked 360s or 400s, no matter how good it was people think it is an emmision only item in spite of the fact they have more potential than the predasessor .
Spell check seemed to be bypassed on this one but at any rate.....I agree with it....and I'll add to it by saying that now we have information that can be shared by the stroke of a keyboard which enables us to more parts, more tuneability, and all around more reason to use a good carburetor like the TQ. There wasn't an information age back in the 70's-80's like there is now and because of this the TQ has come back and IS recognized as a good carb. Many on here will still want a Holley no matter what, but that doesn't make the TQ a bad carb. Again, I have both, and I like both.......
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031778
07/17/11 08:22 PM
07/17/11 08:22 PM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Quote:
Not talking about the air door, alot of what your saying has nothing to do with what i said , not trying too be a jerk, just saying.
Never SAID you were one!! The air door, I brought up as well as the venturies. They are of a more efficient design than the Holleys', that's MY point I was getting at, AFTER agreeing with the post!! I just said MY .
Gotcha
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031780
07/17/11 10:55 PM
07/17/11 10:55 PM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,275
Desert Tracker
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Quote:
Quote:
It's the same reason most morons are into chevs, they just don't know any better! And apart form all this what about all the other problems holleys have, the stripped out threads, the baseplates that are made out of cheese, the fact that the basic design with all the leaks and all the other problems is out of the 50's, the fact that in warm weather they wont start when hot because they boiled over when you turned the engine off, this is a classic, holley couldn't fix it so they gave it a name... "flash boil" the fact that a tiny spec of dirt gets in them and they go haywire. I could go on and on if you guys are happy with junk so be it!
so i guess what should be taken from this thread is what? most morons like chevies and only a select few people in the world know how to tune a thermoquad? i've been playing with cars since the 1960's and as i recall, by then the holley 4150's and 4160's had been out for quite some time. the TQ didn't arrive until around 1969. during the years to follow i don't recall many (if any) people touting the TQ as the greatest carb on earth like i see in this thread today. i wonder why that is? to think no one could ever tune one properly would be a ludicrous thought. the argument that they just weren't as popular without an explanation is just crazy talk. if the argument is that they didn't make as many carbs as holley did, well, that's true, but why? if they were the latest and greatest, Carter surely would have made more. right? they must have some inherent drawback that caused their demise. not only did Chrysler Corporation give up on them, but also the performance crowd of the 70's and 80's etc. so now you'd have one believe that they really are all that and a bag of chips 40+ years later. hasn't history taught us this lesson already? i've owned a few thermoquads over the years and they performed as well as one could expect. okay mileage, no bogs, etc etc. the fact is none of them ever performed as well as a comparable sized 4150 holley. i never cared for the fact that the primary's are so small that you'd have to put the pedal half way to the floor to get the same acceleration as a 4150 does at less than 1/4 throttle. i never cared for that quadrajet sound of the secondary's opening. some thought it sounded cool, although i didn't. it was mostly noise to me. every car i ever had with a thermoquad eventually got replaced with a holley. the cars drove better and were always faster at the race track. perhaps those are just some of the reasons the thermoquads went the way of the dinosaur. oh, and by the way, don't tell me about holleys that have stripped bolt holes or leaks. we all know what caused the threads to strip out. maybe we can talk about cracked and leaking phenolic carb bodies instead, or some of the other inherent design flaws of the lately much revered thermoquad, or maybe you'd rather not...
We can spend ALL DAY AND NIGHT posting about both the Holleys' and the TQs' weaknesses. Sure NEITHER one is perfect, in design nor in performance and efficiency. Bottom line, it comes down to the matter of which type carb works BEST for the combo at hand .
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031781
07/17/11 11:55 PM
07/17/11 11:55 PM
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Joined: Mar 2005
Posts: 2,172 Ohio
theclutcher
top fuel
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top fuel
Joined: Mar 2005
Posts: 2,172
Ohio
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Quote:
Several of each, how deep is your wallet?
My wallet is so deep, you can see Russia when looking at the bottom of it.
Good to see somebody has 'em stashed.... like hens teeth.
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031782
07/18/11 12:04 AM
07/18/11 12:04 AM
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Joined: Jul 2008
Posts: 30,250 Florida STAYcation
dIc dOc Deity !
The village idiot's idiot
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The village idiot's idiot
Joined: Jul 2008
Posts: 30,250
Florida STAYcation
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Quote:
not the best street manors.
....kind-of 'splains most Berri-Crabs ..
Pig fat, fouling spark-plugs and the air, washing cyl walls .... SHALL I continue ? ..
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Re: thermoquad VS. Holley 750 DP
[Re: theclutcher]
#1031783
07/18/11 12:36 AM
07/18/11 12:36 AM
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Joined: Jan 2003
Posts: 42,714 Spokane Washington
ScottSmith_Harms
Mr Wizzard
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Mr Wizzard
Joined: Jan 2003
Posts: 42,714
Spokane Washington
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Quote:
My wallet is so deep, you can see Russia when looking at the bottom of it.
Good to see somebody has 'em stashed.... like hens teeth.
I have a few of them stashed, finding parts to restore them with is murder so I've grabbed all I could find for a while, I find 10 850's for every 1000, both are scarce but the 1000's are getting rediculous!
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031786
07/18/11 06:56 AM
07/18/11 06:56 AM
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Joined: Jun 2008
Posts: 10,847 Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,847
Oakdale CT
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Quote:
I have a few of them stashed, finding parts to restore them with is murder so I've grabbed all I could find for a while, I find 10 850's for every 1000, both are scarce but the 1000's are getting rediculous!
I have a new "aftermarket" electric choke model I picked up at Englishtown swap meet several years ago =)
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Re: thermoquad VS. Holley 750 DP
[Re: theclutcher]
#1031788
07/18/11 09:47 AM
07/18/11 09:47 AM
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Joined: Jan 2003
Posts: 42,714 Spokane Washington
ScottSmith_Harms
Mr Wizzard
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Mr Wizzard
Joined: Jan 2003
Posts: 42,714
Spokane Washington
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Quote:
I have a new "aftermarket" electric choke model I picked up at Englishtown swap meet several years ago =)
You must have 1 of these? Known as "Super Quads", these are not Competition series carbs but rather an over the counter "One size fits all" replacement. Good carbs but not considered to be anything like the Competition Series units.
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031789
07/18/11 12:10 PM
07/18/11 12:10 PM
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Joined: Jul 2010
Posts: 2,091 Delray beach, Florida
Performance Only
top fuel
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top fuel
Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
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how come people are only willing to pay 5.00-25.00 dollars for good cores, yet when you see them advertised for sale everybody wants an arm and 4 legs for them and they're still just good cores? ("supposedly good cores anyway")
Last edited by Performance Only; 07/18/11 12:11 PM.
machine shop owner and engine builder
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Re: thermoquad VS. Holley 750 DP
[Re: dIc dOc Deity !]
#1031790
07/18/11 12:17 PM
07/18/11 12:17 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Quote:
Quote:
not the best street manors.
....kind-of 'splains most Berri-Crabs ..
Pig fat, fouling spark-plugs and the air, washing cyl walls .... SHALL I continue ? ..
Then you need to get better at TUNING them!
I've had a number of 3310 Holley 750 vacuum secondary carbs on everything from a truck 360 to a mild performance 440 and they all peform really well with NONE of the above mentioned traits!
The 360 in my 4x4 powerwagon went from 9 mpg with the tiny 2 bbl. to 11-12 with the Holley. Not great but the thing weighs over 5,000 lbs. and is a full time 4x4. Starts instantly, no fouling, no problems.
The 440 in my '71 'Cuda got 13-14 mpg with a .528 MP cam, headers and Holley 750 on a regular basis. Not spectacular but it started instantly and had great all around performance.
The 318 with 360 heads that I built got 17-18 mpg with a .480 cam, single plane M1 intake, headers, etc. Again, not bad for the combo.
Doc can cry all day long about the Holley's but the simple fact is they are a great carb that is easy to tune and parts are as close as your local O'Reilly's or Autozone.
Thermoquads may have worked well back in the day but, as others here have pointed out, are quickly going the way of the dinosaur.
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Re: thermoquad VS. Holley 750 DP
#1031791
07/18/11 02:07 PM
07/18/11 02:07 PM
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Joined: Jul 2008
Posts: 30,250 Florida STAYcation
dIc dOc Deity !
The village idiot's idiot
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The village idiot's idiot
Joined: Jul 2008
Posts: 30,250
Florida STAYcation
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Quote:
Doc can cry all day long about the Holley's but the simple fact is they are a great carb that is easy to tune and parts are as close as your local O'Reilly's or Autozone.
Thermoquads may have worked well back in the day but, as others here have pointed out, are quickly going the way of the dinosaur.
NO ... gy .... all
...and using YURR logic about parts being more available ... you must be suggesting that we all turn-into Chebby guys ...
...AND the Berri crab is in the same Garden-Grave(yard) as the Plastic Fantastic !
....A N D if the aftermarket gives-us a econ and dependable DPFI system ...NO ONE (in their right minds) ... will use any type of crab ....
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Re: thermoquad VS. Holley 750 DP
[Re: dIc dOc Deity !]
#1031792
07/18/11 03:11 PM
07/18/11 03:11 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Quote:
....A N D if the aftermarket gives-us a econ and dependable DPFI system ...NO ONE (in their right minds) ... will use any type of crab ....
As I mentioned in another post, the NASCAR boys are going to fuel injection next year and the hope is they will develop a system that is simple, works well, and is dead nuts reliable. If so, it may mean cheap FI for all of us!
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Re: thermoquad VS. Holley 750 DP
#1031794
07/18/11 03:41 PM
07/18/11 03:41 PM
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Joined: Jan 2005
Posts: 12,406 Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,406
Kalispell Mt.
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Quote:
Quote:
Quote:
not the best street manors.
....kind-of 'splains most Berri-Crabs ..
Pig fat, fouling spark-plugs and the air, washing cyl walls .... SHALL I continue ? ..
Then you need to get better at TUNING them!
I've had a number of 3310 Holley 750 vacuum secondary carbs on everything from a truck 360 to a mild performance 440 and they all peform really well with NONE of the above mentioned traits!
The 360 in my 4x4 powerwagon went from 9 mpg with the tiny 2 bbl. to 11-12 with the Holley. Not great but the thing weighs over 5,000 lbs. and is a full time 4x4. Starts instantly, no fouling, no problems.
The 440 in my '71 'Cuda got 13-14 mpg with a .528 MP cam, headers and Holley 750 on a regular basis. Not spectacular but it started instantly and had great all around performance.
The 318 with 360 heads that I built got 17-18 mpg with a .480 cam, single plane M1 intake, headers, etc. Again, not bad for the combo.
Doc can cry all day long about the Holley's but the simple fact is they are a great carb that is easy to tune and parts are as close as your local O'Reilly's or Autozone.
Thermoquads may have worked well back in the day but, as others here have pointed out, are quickly going the way of the dinosaur.
All those MPG figures you gave really suck compared to stuff I have had with thermo-quads so I don't get what you are bragging about
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: thermoquad VS. Holley 750 DP
[Re: HotRodDave]
#1031795
07/18/11 03:50 PM
07/18/11 03:50 PM
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Joined: Feb 2005
Posts: 5,221 Branson, Mo.
joedust451
super gas
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super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
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Quote:
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not the best street manors.
....kind-of 'splains most Berri-Crabs ..
Pig fat, fouling spark-plugs and the air, washing cyl walls .... SHALL I continue ? ..
Then you need to get better at TUNING them!
I've had a number of 3310 Holley 750 vacuum secondary carbs on everything from a truck 360 to a mild performance 440 and they all peform really well with NONE of the above mentioned traits!
The 360 in my 4x4 powerwagon went from 9 mpg with the tiny 2 bbl. to 11-12 with the Holley. Not great but the thing weighs over 5,000 lbs. and is a full time 4x4. Starts instantly, no fouling, no problems.
The 440 in my '71 'Cuda got 13-14 mpg with a .528 MP cam, headers and Holley 750 on a regular basis. Not spectacular but it started instantly and had great all around performance.
The 318 with 360 heads that I built got 17-18 mpg with a .480 cam, single plane M1 intake, headers, etc. Again, not bad for the combo.
Doc can cry all day long about the Holley's but the simple fact is they are a great carb that is easy to tune and parts are as close as your local O'Reilly's or Autozone.
Thermoquads may have worked well back in the day but, as others here have pointed out, are quickly going the way of the dinosaur.
All those MPG figures you gave really suck compared to stuff I have had with thermo-quads so I don't get what you are bragging about
Half 2 agree with ya Dave, I do love my holleys no doubt, allways will, But 2 pair them up along with a TQ or QJ for gas mileage, The spreadbore will always win in that department propperly tuned of coarse.
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Re: thermoquad VS. Holley 750 DP
[Re: 68Bullit]
#1031797
07/18/11 04:39 PM
07/18/11 04:39 PM
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Joined: Jul 2010
Posts: 2,091 Delray beach, Florida
Performance Only
top fuel
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top fuel
Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
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Quote:
Some claim they have run them on their cars and eventually replaced them but what does this really add up to????
it could mean a lot of different things. if your suggesting that they're so hard to tune and that's why most people give up on them, then either your right, and everybody but a select few people are just too stupid to tune them. or, perhaps people did learn how to tune them but were happier with something else. MPG is nice for a daily driver, but 1-2 MPG on a hot street strip car or a bracket combo where a holley will run better just seems like a no brainer. as already mentioned, parts for holley's are everywhere. parts for the plastic fantastic, not so much.
machine shop owner and engine builder
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031798
07/18/11 05:03 PM
07/18/11 05:03 PM
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Joined: Jan 2003
Posts: 42,714 Spokane Washington
ScottSmith_Harms
Mr Wizzard
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Mr Wizzard
Joined: Jan 2003
Posts: 42,714
Spokane Washington
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Quote:
how come people are only willing to pay 5.00-25.00 dollars for good cores, yet when you see them advertised for sale everybody wants an arm and 4 legs for them and they're still just good cores? ("supposedly good cores anyway")
What's important to note is which Thermo-Quads you are shopping for, they are not all valued the same. MOST of them are only worth around $25.00 as cores, however a few select TQ part #'s are quite rare/desirable/valuable and can be worth several hundred as cores, so you have to be sure you are comparing apples to oranges when it comes to asking prices.
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Re: thermoquad VS. Holley 750 DP
#1031799
07/18/11 05:20 PM
07/18/11 05:20 PM
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Joined: Jan 2003
Posts: 42,714 Spokane Washington
ScottSmith_Harms
Mr Wizzard
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Mr Wizzard
Joined: Jan 2003
Posts: 42,714
Spokane Washington
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Quote:
Thermoquads may have worked well back in the day but, as others here have pointed out, are quickly going the way of the dinosaur.
Based on the business I have been receiving in the past year or two I totally disagree, if anything they are being rediscovered and their popularity is growing!
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Re: thermoquad VS. Holley 750 DP
[Re: theclutcher]
#1031802
07/18/11 05:58 PM
07/18/11 05:58 PM
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Joined: May 2003
Posts: 15,487 Florida
scratchnfotraction
I Live Here
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I Live Here
Joined: May 2003
Posts: 15,487
Florida
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Quote:
Why not have the best of both worlds. The spreadbore Holley 6210. Now everyone can be happy, not to mention it is a great carb... dbl pumper with 50 cc on secondary, tuneable with small primary.
holley 6210 650cfm dbl pumper spredbore on my 440
also have a holley 4010 duel feed 850 dbl pumper spredbore annular booster...kinda a holleybrock q-jet
holley = gas holes
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031805
07/18/11 06:20 PM
07/18/11 06:20 PM
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Joined: Jul 2008
Posts: 30,250 Florida STAYcation
dIc dOc Deity !
The village idiot's idiot
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The village idiot's idiot
Joined: Jul 2008
Posts: 30,250
Florida STAYcation
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Quote:
Gy3, you just HAD to get Doc GOING, didn't you!!
HYPER- .... now youz knowz me ... I am just gettin' warmed UP !
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031808
07/18/11 06:42 PM
07/18/11 06:42 PM
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Joined: May 2003
Posts: 15,487 Florida
scratchnfotraction
I Live Here
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I Live Here
Joined: May 2003
Posts: 15,487
Florida
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Quote:
Quote:
Quote:
Why not have the best of both worlds. The spreadbore Holley 6210. Now everyone can be happy, not to mention it is a great carb... dbl pumper with 50 cc on secondary, tuneable with small primary.
holley 6210 650cfm dbl pumper spredbore on my 440
also have a holley 4010 duel feed 850 dbl pumper spredbore annular booster...kinda a holleybrock q-jet
holley = gas holes
Glad it WORKS for YOU!!
thats just it...they dont work worth poop so far
I am fixin up a striped down q-jet to try next
I know nothing about tuneing any carbs either
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Re: thermoquad VS. Holley 750 DP
[Re: dIc dOc Deity !]
#1031812
07/18/11 08:57 PM
07/18/11 08:57 PM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,275
Desert Tracker
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HYPER- ......takea' CHILLpill !
WHO HERE is posting like a MADman ? ...
EVERY-ting points at choo ...
Doc, U.Rr.a..ovR..PaYed..Err.IT.aNt!!
Sorry folks, had to talk to Doc in HIS OWN dialect. Its called - "FibGlassic" (and yes, DIEGO please spell-check!). YeRR.. tHe.. OwNLy.. MADMAN here, Doc. Chill-pill? Never take em', DULLS the senses. Unlike you. CHOO..no..wad.I..MEAN!! Besides that, I thought you were also in the know on the the TQ, man. Expand our minds here!!
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031813
07/18/11 09:24 PM
07/18/11 09:24 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031817
07/18/11 11:30 PM
07/18/11 11:30 PM
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Joined: Mar 2005
Posts: 2,172 Ohio
theclutcher
top fuel
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top fuel
Joined: Mar 2005
Posts: 2,172
Ohio
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Quote:
Based on the business I have been receiving in the past year or two I totally disagree, if anything they are being rediscovered and their popularity is growing!
Ever take one apart to see if those boosters could be repro'd and fit into a std TQ?
I imagine some of the tricks that went into the Comp Series design could be incorporated into the std TQ's, No?
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Re: thermoquad VS. Holley 750 DP
[Re: Performance Only]
#1031818
07/18/11 11:47 PM
07/18/11 11:47 PM
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Joined: Mar 2005
Posts: 2,172 Ohio
theclutcher
top fuel
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top fuel
Joined: Mar 2005
Posts: 2,172
Ohio
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Quote:
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Some claim they have run them on their cars and eventually replaced them but what does this really add up to????
it could mean a lot of different things. if your suggesting that they're so hard to tune and that's why most people give up on them, then either your right, and everybody but a select few people are just too stupid to tune them. or, perhaps people did learn how to tune them but were happier with something else. MPG is nice for a daily driver, but 1-2 MPG on a hot street strip car or a bracket combo where a holley will run better just seems like a no brainer. as already mentioned, parts for holley's are everywhere. parts for the plastic fantastic, not so much.
That was my circumstance.
Much info and tech support back then for the Holley, that and cant recall seeing many a racer run one at the track. Dont need much versatility when your at WOT for 1320, hence the change here. Not for lack of tuning ease or ability to do so.
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Re: thermoquad VS. Holley 750 DP
[Re: theclutcher]
#1031819
07/19/11 12:39 AM
07/19/11 12:39 AM
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Joined: Jan 2003
Posts: 42,714 Spokane Washington
ScottSmith_Harms
Mr Wizzard
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Mr Wizzard
Joined: Jan 2003
Posts: 42,714
Spokane Washington
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Quote:
Ever take one apart to see if those boosters could be repro'd and fit into a std TQ?
I imagine some of the tricks that went into the Comp Series design could be incorporated into the std TQ's, No?
I've taken many of them appart but haven't gone into any frankenstein experiments with the boosters, mainly because I haven't really found the need to. I suppose anything is possible if you played with them enough.
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031820
07/19/11 03:22 AM
07/19/11 03:22 AM
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Joined: Sep 2004
Posts: 6,906 IL, Aurora
ademon
master
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master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
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Quote:
Quote:
Ever take one apart to see if those boosters could be repro'd and fit into a std TQ?
I imagine some of the tricks that went into the Comp Series design could be incorporated into the std TQ's, No?
I've taken many of them appart but haven't gone into any frankenstein experiments with the boosters, mainly because I haven't really found the need to. I suppose anything is possible if you played with them enough.
not sure what boosters are being talked about but i have read where you can cut out the outer ring of the booster on the 850 TQ making it about 1000 cfm's, and if you remove the choke plate and related shafts add another 60cfm's. BTW these TQ's are also popular with the big cube Buick guys.
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Re: thermoquad VS. Holley 750 DP
[Re: theclutcher]
#1031824
07/19/11 11:53 AM
07/19/11 11:53 AM
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Joined: Sep 2004
Posts: 6,906 IL, Aurora
ademon
master
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master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
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Quote:
Quote:
Quote:
Quote:
Ever take one apart to see if those boosters could be repro'd and fit into a std TQ?
I imagine some of the tricks that went into the Comp Series design could be incorporated into the std TQ's, No?
I've taken many of them appart but haven't gone into any frankenstein experiments with the boosters, mainly because I haven't really found the need to. I suppose anything is possible if you played with them enough.
not sure what boosters are being talked about but i have read where you can cut out the outer ring of the booster on the 850 TQ making it about 1000 cfm's, and if you remove the choke plate and related shafts add another 60cfm's. BTW these TQ's are also popular with the big cube Buick guys.
To make an 850 Comp series into 1000cfm, cut outer ring?
any 850 TQ, but will need to be jetted up i suspect
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031826
07/19/11 02:05 PM
07/19/11 02:05 PM
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Joined: Jun 2006
Posts: 857 charlotte,nc
pyp1000
super stock
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super stock
Joined: Jun 2006
Posts: 857
charlotte,nc
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here is what i have noticed about this debate: 1) guys who hate thermoquads will never use them 2) demonsizzler is mentioned with glowing reviews in regards to thermoquads 3) demonsizzler does not chime in nor toot his own horn (I have no idea if the 'sizz toots anything else ) 4) I have run out of things to say. 5) demonsizzler; expect a pm from my dad. We need a thermoquad set up, the right way!
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Re: thermoquad VS. Holley 750 DP
[Re: 68Bullit]
#1031827
07/19/11 02:51 PM
07/19/11 02:51 PM
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Joined: Apr 2010
Posts: 1,216 Under My Car
Mopar_Country
pro stock
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pro stock
Joined: Apr 2010
Posts: 1,216
Under My Car
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Quote:
Threads like these draw amazing attention. You get all different takes of course, but I can't help to wonder how many people who talk against the TQ's have ever even used one, let alone taken any time to learn and tune one??? Even just basic tuning
Yup, I was told when working on my TQ to chunk it in the trash can and buy a Holley. I asked why, have you ever run a TQ, the answer was no. The only real world experience this person had was what other people had told him. I run the 850 on my teen and it runs flawlessly. Would I ever run a Holley, maybe, but I got 60 bucks in my carb, when I can buy a quality piece for 60 bucks I might just try it.
As far as mileage comparing 2 318s one with Holley and numerically lower gears gets about the same as mine with numerically higher gears and a TQ, in fact mine might do just a tad better. Same body car.
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Re: thermoquad VS. Holley 750 DP
[Re: Rug_Trucker]
#1031829
07/19/11 03:17 PM
07/19/11 03:17 PM
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Joined: Jan 2005
Posts: 12,406 Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,406
Kalispell Mt.
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Your right Walt I also had a 770 street avenger for a while and it ran just as good but never got near as good of MPG.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: thermoquad VS. Holley 750 DP
[Re: dIc dOc Deity !]
#1031832
07/19/11 05:19 PM
07/19/11 05:19 PM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,275
Desert Tracker
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Quote:
A 1 1/2" primary carb(850) on a small-inch low-rpm MPG project ? ...
Sure, why not? May not have "razor-sharp" performance, but it leaves room for "growth"!! It's mostly about the NEEDED amount of airflow, NOT the TOTAL rating of the carb, Doc. Jetting, float height, choke unloader settings, acc pump settings do have an effect on performance (model depending)..BUT.. you CAN fit the TQ on a 318 and have decent performance!! Personally, a 360 TQ model would be about right for the '18.
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031833
07/19/11 05:30 PM
07/19/11 05:30 PM
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Joined: Nov 2004
Posts: 2,825 Sk. Canada
RemCharger
master
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master
Joined: Nov 2004
Posts: 2,825
Sk. Canada
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I'm like everyone else... have a big steaming pile of tq's which I can't bring myself to throw in the trash. BUT.. this thread does get a guy thinking.... I believe the main reason the tq didn't get the popularity is because they are a pain in the junk to open up and tune or fix problems. Way to much finicky linkage and screws and garbage. If you wanted to start from scratch, its a labour of love. By the time your done , if you sell it you might recoup your money you have into the carb kit. It is a good design, but could have used a couple more mill into engineering.
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Re: thermoquad VS. Holley 750 DP
[Re: HYPER8oSoNic]
#1031836
07/19/11 07:30 PM
07/19/11 07:30 PM
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Joined: Jul 2008
Posts: 30,250 Florida STAYcation
dIc dOc Deity !
The village idiot's idiot
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The village idiot's idiot
Joined: Jul 2008
Posts: 30,250
Florida STAYcation
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Quote:
Quote:
A 1 1/2" primary carb(850) on a small-inch low-rpm MPG project ? ...
Sure, why not? May not have "razor-sharp" performance, but it leaves room for "growth"!! It's mostly about the NEEDED amount of airflow, NOT the TOTAL rating of the carb, Doc. Jetting, float height, choke unloader settings, acc pump settings do have an effect on performance (model depending)..BUT.. you CAN fit the TQ on a 318 and have decent performance!! Personally, a 360 TQ model would be about right for the '18.
HYPER - ...
WE are talking about a low-rpm MPG application ... NONE of what-choo mentioned above really has anything to do with that.
The primary vent SIZE is what matters ... and a 1 3/8 (I would think) would work the bestest there.
I have a 1 3/8 on my Discoverer motorhome(413 power) ...and it has performed GREAT. NO NEED to get into the secondaries uNder normal flat-road cruising operations at around 60 mph.
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Re: thermoquad VS. Holley 750 DP
[Re: dIc dOc Deity !]
#1031837
07/19/11 08:47 PM
07/19/11 08:47 PM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
top fuel
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top fuel
Joined: Nov 2009
Posts: 2,275
Desert Tracker
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Quote:
Quote:
Quote:
A 1 1/2" primary carb(850) on a small-inch low-rpm MPG project ? ...
Sure, why not? May not have "razor-sharp" performance, but it leaves room for "growth"!! It's mostly about the NEEDED amount of airflow, NOT the TOTAL rating of the carb, Doc. Jetting, float height, choke unloader settings, acc pump settings do have an effect on performance (model depending)..BUT.. you CAN fit the TQ on a 318 and have decent performance!! Personally, a 360 TQ model would be about right for the '18.
HYPER - ...
WE are talking about a low-rpm MPG application ... NONE of what-choo mentioned above really has anything to do with that.
The primary vent SIZE is what matters ... and a 1 3/8 (I would think) would work the bestest there.
I have a 1 3/8 on my Discoverer motorhome(413 power) ...and it has performed GREAT. NO NEED to get into the secondaries uNder normal flat-road cruising operations at around 60 mph.
Good for you, that you have chosen that size of primaries for YERR 413 'DISCO!! But Doc... contrary to the nonsence that's rattling in yerr head, I made that point of primary sizes a-WHILE BACK!! Lay off the pipe!!
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: thermoquad VS. Holley 750 DP
[Re: Rug_Trucker]
#1031839
07/19/11 11:29 PM
07/19/11 11:29 PM
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Joined: Jul 2008
Posts: 30,250 Florida STAYcation
dIc dOc Deity !
The village idiot's idiot
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The village idiot's idiot
Joined: Jul 2008
Posts: 30,250
Florida STAYcation
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Quote:
Quote:
A 1 1/2" primary carb(850) on a small-inch low-rpm MPG project ? ...
You never saw the thread?
Yes I saw it RT .. but it never registered that it was a 850. HONESTLY ...I think that some more MPG could be gotten with the 800 carb ... and MAYBE some-more with a reduction of the vent size ON TOP....or on the bottom.
Now to HYPER - ...will he EVER get his ride fixed ? ... ME THIMKS not ! ..
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Re: thermoquad VS. Holley 750 DP
[Re: ScottSmith_Harms]
#1031843
07/21/11 07:03 AM
07/21/11 07:03 AM
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Joined: Jun 2008
Posts: 10,847 Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,847
Oakdale CT
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Quote:
Quote:
I have a new "aftermarket" electric choke model I picked up at Englishtown swap meet several years ago =)
You must have 1 of these? Known as "Super Quads", these are not Competition series carbs but rather an over the counter "One size fits all" replacement. Good carbs but not considered to be anything like the Competition Series units.
Looks like it.
I love the TQ's, going to run one on the GTX again when it comes out to play. The more I tinkered with it the faster the car would go!
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Re: thermoquad VS. Holley 750 DP
[Re: gdonovan]
#1031844
07/22/11 01:25 AM
07/22/11 01:25 AM
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Joined: Jan 2005
Posts: 12,406 Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,406
Kalispell Mt.
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I tried an 800 and it didn't do any different in the MPG department, I think there is a point where atomization only gets so good and the primaries on the 850 are reasonably small. Mabey if I was only concerned with MPG at 50 MPH the smaller one would have showed very small gains but most of my testing was just real world driving in town and on the highway at 70-75 mph. I may be doing another one soon and it will turn less RPM so the smaller carb might show some small improvement.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: thermoquad VS. Holley 750 DP
[Re: HotRodDave]
#1031845
07/22/11 02:57 AM
07/22/11 02:57 AM
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Joined: Sep 2004
Posts: 6,906 IL, Aurora
ademon
master
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master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
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Has anyone on here used a A/F meter when tuning a t-quad, i think this winter i may install my modified stock intake and play around with my 71 t-quads but right off the bat i want to install a A/F meter seems like it would make life easier with the jets, rods, float, sec air door gap, sec air door spring adjustment etc..etc..etc..
Last edited by ademon; 07/22/11 02:59 AM.
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Re: thermoquad VS. Holley 750 DP
[Re: ademon]
#1031846
07/24/11 09:53 AM
07/24/11 09:53 AM
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Joined: Jun 2008
Posts: 10,847 Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,847
Oakdale CT
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Quote:
Has anyone on here used a A/F meter when tuning a t-quad
Only since the early 90's!
O2 sensor and gauges takes a lot of guesswork out of tuning and the gauges are certainly cheaper than 20 years ago.
Some folks will state you need a wide-band sensor for proper tuning, this just isn't so unless you are on the ragged edge at WOT in my honest opinion.
I have tuned engines running 30 psi on gas with narrow band factory sensors without fail, now that can get hairy fast if you screw up.
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