Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: StealthWedge67]
#443827
08/26/09 05:45 PM
08/26/09 05:45 PM
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Joined: Jan 2003
Posts: 4,150 lewiston, ID
cornucopia
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Joined: Jan 2003
Posts: 4,150
lewiston, ID
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Quote:
Not that it can't work, but you are in a long list of guys that have faught with the Eddy 750 off-idle stumble. Do a search on it, you'll be amazed. I tried every setting and rod / jet combo immaginable. Tried two different carbs, same issue with both. Went to a Holley 750, Sooooo much better.
I agree %100! my 750 eddy was stumble city. I tried everything. fixed it by buying a 3310 holley...
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: 70Sbird]
#443828
08/26/09 05:50 PM
08/26/09 05:50 PM
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Joined: Feb 2003
Posts: 12,675 Columbia, CT
moper
I Live Here
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I Live Here
Joined: Feb 2003
Posts: 12,675
Columbia, CT
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Some basic numbers... Initial timing should be 12-16°. You will have to limit the mechnical advance in the distributor which is adjustable. You want a mechanical advance of 20°. So your total, checked with either a tming light that has the advancing function, or a timing tape installed on the balancer will be 32-36. This is with the vacuum advance disconnected and the port on the carb plugged. On the carb, I would use the tuning book and go two steps richer on power and cruise from the correct factory installed jet and rod combo. Use the colored springs that match the vacuum level on a gage when idling in gear after the timing is set. You will be readjusting the idle speed, mixture, and probably the step up springs will be changed again when everything else is close. If once you have the rest dialed in, it still has a hesitation, then you can add the squirtor. The deal is tho... squirtor have NO effect on fuel volume being sprayed. Only the time it takes to shoot it all out. Going larger may cover the bog but it will be lean at part throttle acceleration because the accelerator pump will be empty before the air has picked up enough speed thru the boosters to draw fuel properly. This is why I use them as a last resort, and why I almost never have to change them. Even on Holleys. Just stay focussed and you will not believe how much nicer an old "non-rocket science" car can run.
Well, art is art, isn't it? Still, on the other hand, water is water! And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now, uh... Now you tell me what you know.
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: 70Sbird]
#443829
08/26/09 07:56 PM
08/26/09 07:56 PM
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Joined: Jan 2003
Posts: 5,270 Missouri
MY340
master
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master
Joined: Jan 2003
Posts: 5,270
Missouri
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Quote:
OK, I got the carb off last night and pulled the jets out to verify the base combo I'm working with. As I was surprised with the rods being changed, so were the jets. I had .104 main jets, combining this with the rods, I found this combination on the Edelbrock calibration chart and this combo represente two steps lean on the cruise mode and three steps lean on the power mode!
Now, would that cause a lean off idle condition? I'm probably going to start from scratch at this point and begin as recommended above, new spark plugs and reset base timing (MP electronic ignition so no points)and set the carb at baseline, or possibly a step or two rich. or is there a better place to start other than the baseline factory settings? I'm still thinking I probably need to move up to the .043 acc pump nozzles from the .035s on there now
That's way too lean for a BB Mopar!!! Somebody might have been running that carb on a stock Chevy SB!!! Like I said before any carb needs to be properly setup for the motor/combo.
The stock 113/107 jets, 71/47 rods and .035 squirters on the 1407 Eddy 750 cfm carb is just about perfect for my mildly built 360. Probably alittle too rich as my MPG isn't great but I'll coorect that as time permits. I had too much pump shot and went to the middle hole plus bumped intial timing up 4 degrees. NO HESITATION on my carb. Sorry all you Holley guys!
1970 FE5 Duster 360/904/3.91's SOLD
1973 TB3 SpaceDuster 340/4spd/4.10's SOLD
Moparless for now but when the opportunity is right I'll have another one.
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: MY340]
#443830
08/26/09 09:20 PM
08/26/09 09:20 PM
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Joined: Nov 2004
Posts: 1,760 Port Alberni, British Columbia
MoparDonny
top fuel
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top fuel
Joined: Nov 2004
Posts: 1,760
Port Alberni, British Columbia
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I thought he said it was a 1411 carb not a 1407. 1411's are leaner to start with. From Edelbrock: EDELBROCK PERFORMER SERIES 750 CFM, ELECTRIC CHOKE CARBURETORS CALIBRATED FOR ECONOMY WITH PERFORMANCE Designed for 402 c.i.d. and larger engines with Edelbrock Performer manifolds and other brands of similar design, these carbs are recommended only for stock to Performer level applications. They are not recommended for use on RPM or Torker II intake manifolds. Calibrated 2% leaner than #1407. Provides excellent fuel economy when used on 454 c.i.d. Chevy and 460 c.i.d. Ford with Performer manifold. Includes both timed and full vacuum ports for ignition advance. Comes with: Metering Jets - Primary .110, Secondary .107; Metering Rods - .075 x .047; Step-Up Spring - orange (5" Hg). With that, I had borrowed a 1407 from a friend a few years ago and out of the box I hated it. Maybe it needed some tuning, maybe not. It bogged, had poopy throttle response, I don't think the full throttle power was very good either. He runs that carb on a warmed 340 and says he loves it . It runs 13.20 in a 69 dart. Just a story i thought I'd share, I don't mind the Eddy's at all but I don't run one on my stuff.
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Ray440]
#443831
08/27/09 11:12 PM
08/27/09 11:12 PM
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Joined: May 2003
Posts: 6,562 Downtown Roebuck Ont
Twostick
Still wishing...
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Still wishing...
Joined: May 2003
Posts: 6,562
Downtown Roebuck Ont
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Quote:
Has anyone tried this before? Below the accelerator discharge squirter there is a small weight and a check ball. Buddy of mine had removed the weight and his stumble is gone. Leave the check ball in.
I think that is the same cure Herb McCandless talked about at his Carlisle seminar.
Kevin
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Twostick]
#443832
08/28/09 08:15 AM
08/28/09 08:15 AM
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Joined: Feb 2003
Posts: 2,810 Sobieski Wi
bee1971
master
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master
Joined: Feb 2003
Posts: 2,810
Sobieski Wi
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I remember talking to Edelbrock a few years back , there tech line , on that very same subject Thats when they sent me the larger squirter for free - Still didnt solve the problem But interesting to say the least - I gave up many moons ago - Bottom line in the end , like i stated earlier , even if you got the stumble fixed , and threw every spring ,metering rod , jet , squirter blah blah blah at it , you still have a carb that doesnt perform across the board Did anyone read my last post about the dyno #s ??? And you dont realize it until you switch over to a Holley or a Edelbrock 800 series Man there is so may threads on the subject - Enjoy https://board.moparts.org/ubbthreads/show...part=1&vc=1https://board.moparts.org/ubbthreads/show...part=1&vc=1https://board.moparts.org/ubbthreads/show...part=1&vc=1
1971 Dodge Charger Superbee 2011 Ram Sport 1500 Quad Cab Deep Water Blue Loaded Siberian Huskies
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: bee1971]
#443833
08/28/09 09:43 AM
08/28/09 09:43 AM
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Joined: Feb 2003
Posts: 2,810 Sobieski Wi
bee1971
master
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master
Joined: Feb 2003
Posts: 2,810
Sobieski Wi
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Some more info that i ran into in the past
The edelbrock carbs have a lean off idle problem, i only recommend using a 650 or lower cfm edelbrock on any application because of this but:
the idle channel restriction (ICR) is too small for the idle system so the idle system runs out of fuel flow before you get into the main circuit. look in the carb owners manual and you can see where it is. we remove the brass restriction over the ICR and then enlarge the ICR a few thousands of a inch at a time to make the idle and off idle system more active. this workd very well on the 600 performer and 650 cfm thunder but on the 750 it only helps since the rest of the idle system passages are too small. these changes have been done to the 800 cfm edelbrocks but it is not enough to solve the problem (in my opinion)if you want to see pictures of this the july 2006 issue of Corvette Fever has a article called tuning to perfection with more detail in it.
you can see this lean at off idle condition with tools such as a wide band oxygen sensor based air/fuel meter or a 5 gas exhaust gas analyzer.
i hope this helps henry @ oles carb
1971 Dodge Charger Superbee 2011 Ram Sport 1500 Quad Cab Deep Water Blue Loaded Siberian Huskies
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: bee1971]
#443834
08/28/09 09:49 AM
08/28/09 09:49 AM
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Joined: Oct 2007
Posts: 288 Birmingham, England
Mick70RR
enthusiast
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enthusiast
Joined: Oct 2007
Posts: 288
Birmingham, England
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That's one of the mods I tried on my 1407 before I god rid of it. Helped a little but it didn't get rid of the off-idle bog.
1970 Road Runner
505 cid
MCH CNC ported Stealth heads
MP 528 camshaft
4 speed
GV overdrive
11.98 @ 117 on street treads
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Dougsmopars]
#443838
08/28/09 09:45 PM
08/28/09 09:45 PM
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Joined: May 2004
Posts: 1,031 South Jersey
kruger
Yours Too!
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Yours Too!
Joined: May 2004
Posts: 1,031
South Jersey
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Quote:
I only have 2 thoughts on "there's a reson why performence cars use Holley" 1 is there quicker to mess with at the track, second when i go to the drags i see more Demons and Barry Grants and other Holley Knock off's then Holley's. And i asume your a newbie to Mopar. For many years Mopar used Carters on 90% of there muscle cars. There are 2 camps here. Those that love Holleys and those who don't. I really wish you Holley guys would get off it. If you like them more power to you. There are just as many guys out there who have had plenty of trouble with Holleys. There is no such thing as a perfect carb. Every car needs to get the carb set up for that engine.
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Dougsmopars]
#443839
08/29/09 09:14 AM
08/29/09 09:14 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:
I only have 2 thoughts on "there's a reson why performence cars use Holley" 1 is there quicker to mess with at the track, second when i go to the drags i see more Demons and Barry Grants and other Holley Knock off's then Holley's. And i asume your a newbie to Mopar. For many years Mopar used Carters on 90% of there muscle cars. There are 2 camps here. Those that love Holleys and those who don't. I really wish you Holley guys would get off it. If you like them more power to you. There are just as many guys out there who have had plenty of trouble with Holleys. There is no such thing as a perfect carb. Every car needs to get the carb set up for that engine.
no I'm not new, Just stating a fact. They work better. Mopar used carters because they were probaby cheaper. Decent carb, but I've used both and tuned a bunch. You just get much more out of a holley.
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Mr.Yuck]
#443840
08/29/09 09:32 AM
08/29/09 09:32 AM
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Joined: Jan 2003
Posts: 75,012 U.S.S.A.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,012
U.S.S.A.
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Quote:
There's a reason all performace cars use holleys.....
Care to expand on that statement, all muscle car era performance cars , performance cars before the fuel injection era or current day not new performance cars ?
One thing you'll get from moparts is people telling you what to do instead of answering your question .
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Mr.Yuck]
#443841
08/30/09 01:10 AM
08/30/09 01:10 AM
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Joined: May 2004
Posts: 1,031 South Jersey
kruger
Yours Too!
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Yours Too!
Joined: May 2004
Posts: 1,031
South Jersey
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Quote:
Quote:
I only have 2 thoughts on "there's a reson why performence cars use Holley" 1 is there quicker to mess with at the track, second when i go to the drags i see more Demons and Barry Grants and other Holley Knock off's then Holley's. And i asume your a newbie to Mopar. For many years Mopar used Carters on 90% of there muscle cars. There are 2 camps here. Those that love Holleys and those who don't. I really wish you Holley guys would get off it. If you like them more power to you. There are just as many guys out there who have had plenty of trouble with Holleys. There is no such thing as a perfect carb. Every car needs to get the carb set up for that engine.
no I'm not new, Just stating a fact. They work better. Mopar used carters because they were probaby cheaper. Decent carb, but I've used both and tuned a bunch. You just get much more out of a holley.
oooops!Sorry Swingin72,I know your not new to Mopars.
I use both Holleys and Eddy's,though I dont use the Eddy's for street apps I do use the 750 Eddy's on a crossram with no problems(WOT). Guess it just comes down to preference not fact?
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: kruger]
#443842
08/30/09 03:28 AM
08/30/09 03:28 AM
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Joined: May 2004
Posts: 4,920 Joplin, MO USA
Robbins
master
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master
Joined: May 2004
Posts: 4,920
Joplin, MO USA
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Well, I hoping that mine will work out good for my 446 in my 86 RC. It has a four hole 1 in spacer under it.
Moparlee
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Mr.Yuck]
#443843
08/30/09 10:46 AM
08/30/09 10:46 AM
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Joined: Jul 2006
Posts: 4,319 Puyallup, WA
StealthWedge67
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Posts: 4,319
Puyallup, WA
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Quote:
no I'm not new, Just stating a fact. They work better. Mopar used carters because they were probaby cheaper. Decent carb, but I've used both and tuned a bunch. You just get much more out of a holley.
Lets clarify: we're not talking about Carters, we're not even talking about all Eddy performer series. This is an issue that is specific to the 1407 / 1411 Edelbrock 750cfm carbs. The 625's and the 800 AVS Thunders seem to get rave reviews. These 750 performers are the ones that seem to have issues. As far as Carters and others, that's purely preference, as I've never heard any evidence that there was real issues with any of the others, like we see in the 750's.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: StealthWedge67]
#443844
08/31/09 09:06 AM
08/31/09 09:06 AM
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Joined: Jan 2003
Posts: 5,270 Missouri
MY340
master
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master
Joined: Jan 2003
Posts: 5,270
Missouri
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Am I still the only guy that likes his 1407 Eddy? FWIW I also use a 4-hole 1" spacer under the carb. Hooked up the manual choke and now even cold starts are easy. My last post on this thread.
1970 FE5 Duster 360/904/3.91's SOLD
1973 TB3 SpaceDuster 340/4spd/4.10's SOLD
Moparless for now but when the opportunity is right I'll have another one.
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Re: off idle stumble with Edelbrock 750 - suggestions?
[Re: Mr.Yuck]
#443846
08/31/09 01:29 PM
08/31/09 01:29 PM
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Joined: Jan 2003
Posts: 75,012 U.S.S.A.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,012
U.S.S.A.
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Quote:
They are fine carbs, just not for racing
Don't tell that to the guys that race NSS with MAXWEDGE cars
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