Previous Thread
Next Thread
Print Thread
Edelbrock Carbs #1682510
10/05/14 11:06 PM
10/05/14 11:06 PM
Joined: May 2005
Posts: 127
Missoula, Montana
ChadP Offline OP
member
ChadP  Offline OP
member

Joined: May 2005
Posts: 127
Missoula, Montana
Engine - 440, mild build, 10.0 to 1. Carb is an Edelbrock 750, and I'm done with it. Been a pain since day 1. After buying it, I read on the forums where many others have had similar problems with 750. I realize there are Holley lovers who will criticize this direction - but thinking of replacing the 750 with Edelbrock 600. Car is a 4-speed 65 B-Body with 3.09 first gear in 833 trans, and 2.76 rear. (Was auto car but converted). Good cruiser, and with the 3.09 first gear, OK getting started. With a Holley 700 dp engine did 385 hp on dyno when new. Has about 5k miles on it. The question - for a car that's used primarily cruising on the highway, will the 600 be enough carb?


'65 Coronet 500
Re: Edelbrock Carbs [Re: ChadP] #1682511
10/05/14 11:15 PM
10/05/14 11:15 PM
Joined: Mar 2005
Posts: 1,406
New Jersey, USA
Y
yella71 Offline
pro stock
yella71  Offline
pro stock
Y

Joined: Mar 2005
Posts: 1,406
New Jersey, USA
It will be fine but you'll lose a bunch of power


71 challenger convertable, 64 sport fury 383 ci with factory air 99 sebring convertable 89 CTD pup
Re: Edelbrock Carbs [Re: yella71] #1682512
10/05/14 11:57 PM
10/05/14 11:57 PM
Joined: Mar 2005
Posts: 792
Earth
R
Rob C Offline
super stock
Rob C  Offline
super stock
R

Joined: Mar 2005
Posts: 792
Earth
I have an engine question for you that relates to your issue.
What cam do you have in there? (Specs?)
Are your heads ported? Headers?

The smaller 600 will increase throttle response a lot. The loss of HP will be on the top end. How much time do you spend there? If it is not a lot, then the smaller carb can be done. I would however choose the Thunder 650 AVS hybrid since the secondary air door is tuneable and will avoid the bog that happens when the AFB suddenly has a W.O.T. application.

Otherwise, the Holley will do just fine. And I would also repeat the use of a double pump for sure.

Re: Edelbrock Carbs [Re: Rob C] #1682513
10/06/14 12:23 AM
10/06/14 12:23 AM
Joined: May 2005
Posts: 127
Missoula, Montana
ChadP Offline OP
member
ChadP  Offline OP
member

Joined: May 2005
Posts: 127
Missoula, Montana
Cam:
Gross lift at cam - intake 317, exhaust 333. Degree of duration intake 220, exhaust 230. Running clearance...valve lift intake 475, duration 270. Exhaust lift 500, duration 285. Lobe center 110, center line 108.

Exhaust stock '69 HP manifolds. Intake manifold, stock. Heads, stock 906, no porting.


'65 Coronet 500
Re: Edelbrock Carbs [Re: ChadP] #1682514
10/06/14 12:37 AM
10/06/14 12:37 AM
Joined: Mar 2007
Posts: 3,300
Northern Indiana
Dunnuck Racing Offline
master
Dunnuck Racing  Offline
master

Joined: Mar 2007
Posts: 3,300
Northern Indiana
I have a 440 on my dyno now and have tested several carburetors on it. At 440 horsepower it was pulling 630 cam through the airflow meter. With a 650 carburetor it has a much nicer torque curve than with a larger carburetor. I have done similar tests on other engines and I can tell you with certainty a 600 will be fine. You may lose 5 horsepower at the very top of your rpm range over a larger carburetor but everywhere else will be much nicer.
Keith

Re: Edelbrock Carbs [Re: Dunnuck Racing] #1682515
10/06/14 09:27 AM
10/06/14 09:27 AM
Joined: Nov 2004
Posts: 25,050
Texas
GoodysGotaCuda Offline
5.7L Hemi, 6spd
GoodysGotaCuda  Offline
5.7L Hemi, 6spd

Joined: Nov 2004
Posts: 25,050
Texas
The 650 Thunder AVS was a very good carb to me, only pulled it to go EFI.


1972 Barracuda - 5.7L Hemi, T56 Magnum 6spd - https://www.facebook.com/GoodysGotaHemi
2020 RAM 1500
[img]https://i.imgur.com/v9yezP9.jpg[/img]
Re: Edelbrock Carbs [Re: GoodysGotaCuda] #1682516
10/06/14 11:01 AM
10/06/14 11:01 AM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
i've been playing with edelbrock carbs the last year or so. i do have a 750 i'm playing with now; 600's and 800's previously. one thing i've noticed is the calibration on them seems to be too rich. i've also noticed some inconsistencies in the primary cluster air bleeds and idle jets. it's not difficult to make things better. it's just different than the conventional "holley" method of making changes.

Re: Edelbrock Carbs [Re: Dunnuck Racing] #1682517
10/06/14 11:17 AM
10/06/14 11:17 AM
Joined: Jan 2003
Posts: 11,894
Benton, IL.
D
DaveRS23 Offline
Special needs idiot
DaveRS23  Offline
Special needs idiot
D

Joined: Jan 2003
Posts: 11,894
Benton, IL.
Quote:

I have a 440 on my dyno now and have tested several carburetors on it. At 440 horsepower it was pulling 630 cam through the airflow meter. With a 650 carburetor it has a much nicer torque curve than with a larger carburetor. I have done similar tests on other engines and I can tell you with certainty a 600 will be fine. You may lose 5 horsepower at the very top of your rpm range over a larger carburetor but everywhere else will be much nicer.
Keith




Has a Street Demon been part of your testing?


Master, again and still
Re: Edelbrock Carbs [Re: ChadP] #1682518
10/06/14 11:43 AM
10/06/14 11:43 AM
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert Offline
Circle Track
Happy Birthday RapidRobert  Offline
Circle Track

Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
Quote:

Engine - 440, mild build, but thinking of replacing the 750 with Edelbrock 600. The question - for a car that's used primarily cruising on the highway, will the 600 be enough carb?


I had a C boat with a 350 horse stock 440 which came with a PO installed 1406 600 eddy & it ran/cruised fine. They (the 1406's elec choke ones not the 1405 manual choke ones) come lean so you would need the strip kit to richen the cruise step at least. eddys can have problems with the low/fluctuating vacuum from wild cams if that is the case with your cam


live every 24 hour block of time like it's your last day on earth
Re: Edelbrock Carbs [Re: RapidRobert] #1682519
10/06/14 09:05 PM
10/06/14 09:05 PM
Joined: Jan 2003
Posts: 1,436
Oklahoma City OK
Cudajon Offline
pro stock
Cudajon  Offline
pro stock

Joined: Jan 2003
Posts: 1,436
Oklahoma City OK
All your gearing is really tall so running a high cfm carb will cause problems revving up. The Eddy and Carters use what they call "Aux valves and weights" (its those butterflys located above the secondary butterflys)to limit the the air flow to the secondarys till the engine rpm picks up and can handle it. (The thermoquad, avs, and quadrajet have a something similar). I drill holes in the weights on those if I want them to open faster, and to slow them down I put round fishing weights in those holes. Theres no danger of them falling into the carb because the weights work in their own well, anyway I've never had one come out because I peen them pretty good. If you have the bread get a 600cfm, they're good carbs, but if you like the idea of 750cfm try the lead shot idea. Doesn't take a lot, normally one 1/4 inch Dia. in each weight.

Re: Edelbrock Carbs [Re: Cudajon] #1682520
10/06/14 09:44 PM
10/06/14 09:44 PM
Joined: Jan 2003
Posts: 3,967
S.I. N.Y.
1MYTGTX Offline
master
1MYTGTX  Offline
master

Joined: Jan 2003
Posts: 3,967
S.I. N.Y.
Recently installed a Thunder Series 800 AVS in place of my 750 VS Holley on my 440 & couldn't be happier


1MYTGTX
Re: Edelbrock Carbs [Re: Cudajon] #1682521
10/06/14 09:52 PM
10/06/14 09:52 PM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
the edelbrock 750 is identical in venturi and throttle bore size to the '67 440hp carb; which wasn't none too big. only practical difference is air horn size. the '68 and up 440hp had slightly larger secondary venturi with the same throttle bore size. one of the mopar mags, mopar action i think, did a flow test on the larger '68 and up avs and i think they only got 715cfm. i seriously doubt the 750 edelbrock is near 750 cfm. probably 700 would be more accurate. another thing to keep in mind is that the '64 s/s wedges ran two carbs the same size as the edelbrock 750. i don't get lost in any of the cfm hype. it's more a marketing ploy anymore. the velocity controlled secondaries keep people out of trouble. the real key is calibration and to re-work afb's one has to get their head out of the holley box.

Re: Edelbrock Carbs [Re: lewtot184] #1682522
10/06/14 09:55 PM
10/06/14 09:55 PM
Joined: Apr 2012
Posts: 18,880
-
R
RSNOMO Offline
Moparts Torchbearer
RSNOMO  Offline
Moparts Torchbearer
R

Joined: Apr 2012
Posts: 18,880
-
Quote:

the real key is calibration and to re-work afb's one has to get their head out of the holley box.




Uh-huh...

Re: Edelbrock Carbs [Re: ChadP] #1682523
10/07/14 11:37 AM
10/07/14 11:37 AM
Joined: Jan 2003
Posts: 28,063
Irving, TX
feets Offline
Senior Management
feets  Offline
Senior Management

Joined: Jan 2003
Posts: 28,063
Irving, TX
The 750 AFB has a mixed reputation. Years ago it was found that there were some issues with the Eddy design. Simple scaling up of the 600 didn't allow for the best performance. Jetting and rod adjustments helped but didn't completely cover the problem.

Personally, I prefer the AFB. When I sold the hot rod I had dropped a 600 cfm AFB on the 440. The throttle response was indeed impressive and there wasn't much loss in power up top. It made for a great driving car.
My Imperial also wears a 600 cfm AFB on it's 440. it's not exactly a performance machine but it's a lot more car than what you're pushing around.


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
Re: Edelbrock Carbs [Re: feets] #1682524
10/07/14 11:46 AM
10/07/14 11:46 AM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
Mr.Yuck  Offline
Not enough dumb comments...yet

Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Buy a used 750DP, add rebuild kit, 6.5PV, 74/80 jets, 31 squirters and enjoy. No way I'd run a 600 carter on a mild 440. It's hardly big enough for a mild 340. Why people waste their time messing with Eddy 750's is beyond me. Unless you are stuck w/ them for class reasons (and typically you run TWO) or something. If you must have an Eddy, go w/ the 800 thunder.


[IMG]http://i66.tinypic.com/pui5j.jpg[/IMG]
Coming soon!!!!
Re: Edelbrock Carbs [Re: Mr.Yuck] #1682525
10/07/14 11:52 AM
10/07/14 11:52 AM
Joined: Jan 2003
Posts: 28,063
Irving, TX
feets Offline
Senior Management
feets  Offline
Senior Management

Joined: Jan 2003
Posts: 28,063
Irving, TX
The 800 Thunder is a better choice than the 750 assuming your engine can handle the flow.

Remember, we're not talking about a RACE engine or even much of a hot rod. He stated the car was a cruiser. The smaller carb will give excellent response and good performance.

As for the 750DP? I'm not a racer and have no use for those carbs. I've had my share of them and even built one around a ProForm body. It went down the road and I moved back to the AFB.


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
Re: Edelbrock Carbs [Re: feets] #1682526
10/07/14 12:56 PM
10/07/14 12:56 PM
Joined: Sep 2014
Posts: 1,396
Central Pa
M
moparjim79 Offline
pro stock
moparjim79  Offline
pro stock
M

Joined: Sep 2014
Posts: 1,396
Central Pa
Go with an Edge Brick 750

Re: Edelbrock Carbs [Re: ChadP] #1682527
10/07/14 01:27 PM
10/07/14 01:27 PM
Joined: Aug 2013
Posts: 518
Georgia
S
Steve Bryant Offline
mopar
Steve Bryant  Offline
mopar
S

Joined: Aug 2013
Posts: 518
Georgia
I took the Eddy 750 off my mild 440 about six months ago after many weeks of tuning with an A/F sensor and gauge. I moved up to the Eddy 800 1413 and it was a night-and-day difference. No low-end stumble and the A/F mixture was perfect right out of the box.

There is something about the accelerator pump and the 750 that doesn't work well with many big blocks. I was able to tune most of the stumble out but I never could get it to smooth out completely. I sold the 750 on Ebay and bought the 1413 and the car runs like a top now.

Re: Edelbrock Carbs [Re: Steve Bryant] #1682528
10/07/14 01:36 PM
10/07/14 01:36 PM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
Quote:

I took the Eddy 750 off my mild 440 about six months ago after many weeks of tuning with an A/F sensor and gauge. I moved up to the Eddy 800 1413 and it was a night-and-day difference. No low-end stumble and the A/F mixture was perfect right out of the box.

There is something about the accelerator pump and the 750 that doesn't work well with many big blocks. I was able to tune most of the stumble out but I never could get it to smooth out completely. I sold the 750 on Ebay and bought the 1413 and the car runs like a top now.


the 1407 i have has a 35 squirter which is too big for driving and the 113 primary jets are ridiculously big. i also have concern about the .046 idle air bleed in combination with a .037 idle jet. they're fixable but need some patience and a little working knowledge of carbs.

Re: Edelbrock Carbs [Re: DaveRS23] #1682529
10/07/14 11:43 PM
10/07/14 11:43 PM
Joined: Mar 2007
Posts: 3,300
Northern Indiana
Dunnuck Racing Offline
master
Dunnuck Racing  Offline
master

Joined: Mar 2007
Posts: 3,300
Northern Indiana
Quote:

Quote:

I have a 440 on my dyno now and have tested several carburetors on it. At 440 horsepower

Has a Street Demon been part of your testing?




Yes it has,
It did real well at the 440 horsepower level. When I ported the heads and went with a bigger camshaft, these smaller carburetors were too small.
But on the lower horsepower build the Street Demon 625 was worth some low end torque. It wasn't quite as impressive as it was on my 360 mule though. I think it had to do with the Thumper cam in that 360 having weaker vacuum signal than this 440 with a smaller cam
Keith







Powered by UBB.threads™ PHP Forum Software 7.7.1