I run a mopar 500 crate engine with torker 440 inlet and a edelbrock 750 carb.
The car runs great on part throttle right thru to flat out.
Tickover is lumpy but acceptable.
When i apply a light throttle from tickover the engine doesn't want to pick up and stutters,if i give it more gas it will pick up straight away.
I've got a calibration kit to go with the carb but am unsure where to start???
Any suggestions please?

There should be instructions with the cal- kit.
Try richening the mid range on the primaries.. That is the fatter part of the rods. find some a little smaller.

Over the years, there have been many posts specifically regarding the Eddy 750 and it's off idle spudders. I had a 440 in a GTX with the 750; generally it ran great...but it had off-idle spudder/ slight hesitation. My understanding is 800's do not have these issues, nor do 650's Personally for my 416 sb stroker, I went Quick fuel 780...I'm very happy

Any suggestions please?



Yep - Ebay or Craigslist

Honestly , a 500 crate motor with an Edelbrock 750
WOW - Who gave you that carb suggestion ??? Chevrolet

Wait till you get a real carb on there - You have no idea what your missing and please dont waste your time or money with the calibration kit

Thanx Scott

here's you problem...500 + 750 eddy = dog. Junk it and get a real carb. I'd start w/ a 850 DP and go from there.

Assuming you've got enough initial advance and you've tryed all 3 positions on the linkage rod. Pull the caps off the metering rod pistons and fire it up. Check to see if the pistons are fully seated and not fluttering when idling. If they flutter, install a weaker set of springs. Dave

I'm a big fan of the 750 AFBs, so I'd love to see you get it tuned. Follow Quickd100's advise.
That said, I do think that the 750 is too small for the 500.
I finally had to make the switch to Holley when my 440 became a 505".
Good luck, whichever way you go.
Cheers!

Don't waste your time with that carb.Ditch it at your earliest opportunity.If a Holley HP 950 isn't in the budget then try a 850DP as suggested above.Eddy's are great for economy and that's about it.I use one personally on my jet-boat very good for reliablity/economy; swapped over to a Holley(noticeable performance increase).

Hi,
Thanks to everybody who has chimed in so far.
I realize that for outright performance the Holley DP was the way to go
I fitted the Edelbrock for 3 reasons.
1 I wanted the engine to look as stock as possible.
2 I picked it up brand new in the box for a good price
3 The MPG,fuel is £6 ($12) a gallon in the uk.
What was said by Fox about richening the mid range,yep i can see that and will give it a try.

What was described by Mopar Dan is exacly what my car does and interestingly when the car was a 383 i ran a smaller Edelbrock with no probs.

I'll also try the advice given by Quickd100 and see how i get on,there's some different color coded springs in the kit.

Many thanks to all of you
Cheers
Simon

run a vacume gauge on the car at idle. whatever the redeaing is divid by 2 and that will tell you the correct metering rod spring. example a engine with 14 inchs of vac will run best with a spring that opnes at 7 inches hg of vacume (i believe pink spring) as far as jetting and metering rods check the plugs

Thanks Nick i will try this also.
The engine does not make a whole lot of vacuum at idle

Definately get something else. Myself and someone I know are having the same issues right now. I couldn't be anymore disappointed in this carb. It's only 2 years old with maybe 5,000miles on it.


I'll be moving to a Holley when I can.

You will never tune out the stumble , they have isues with placment of the venturies and cannot be corrected , I also went with a ported Holley and never looked back . Was like bolting on fuel injection , no kidding .And I am a current master , Chysler tech , so I do know what Im talking about .

Not mentioned (AGAIN! ) but the Eddys (and all aftermarket AFB's) benefit from a 4 hole spacer under it. It can be a thick gasket, as long as it's a 4 holer.

I always use AFB's, and love them! I have a pile of 1/4" (6mm) cardboard 4 holers that I stack on the intake until I find the right blend, then I buy a phenolic spacer that matches that dimmension.

My 360 needed 1.25" (30mm) worth, my poly 318 needed 1/4" (6mm), and my 440 needed 1" (24mm) spacers.

They barely run without them, and Eddy's site states the use of the 4-holer.

Cheers!

Yes, the guy that designed the boosters was secretly working for holley or on drugs, or both. I've been replacing the boosters with old 750 carter boosters on mine. You can tune the hesitation out of them without going that far though. Dave

But but but the 800 will run right out of the box.
AndyF made over 500 hp with an 800 Edelbrock.
The reason you got the 750 cheap is the problem you are having now.
R.

I agree that you need more carb. Get the biggest Edelbrock you can. The Thunder 800AVS would be my choice. You will have part throttle/transition issues becasue that long stroke and fairly mild heads are moving more air at different speeds than the airflow window a 750 is really designed to meter. IMO, an engine of that size should have started with an HP 950 or the Street Avenger 870. The avenger when flowed the same as an Edelbrock is 950cfm. And that is small for a stroke of 4.15". But i see your point about visuals. Eventually tho, the carb simply can't do the job right, and transition and part throttle is where you'll feel it. I's also imagine you have not dyno'd it and seen how the power drops off a ledge when it can't suck in enough air.

How about a Quadrajet with a Cliff Ruggles tune on it? Is that total sacrilege here?

I have an Edelbrock 750 on the 455 in my GTO that runs like crap because of a serious OFF-IDLE STUMBLE that I haven't been able to eliminate. I've tried all the tuning kit parts as well as mounting wires in the idle air bleeds. Nothing works.

So I read the Cliff Ruggles book and did some online research and decided to give a later Q-jet a try. I haven't rebuilt it yet but I got one from a yard to rebuild.

Anyway, a Q-jet seems similar to a Thermoquad in that it has small primaries and huge secondaries so maybe it's not that out of place on a MoPar...

Q-jets can run awfully hard. Be aware that there are two sizes, the larger one coming on engines like the Eldorado 500 cubic inch.

Any carb can be made to run if properly tuned, except it seems the Edelbrock 750 is the exception to the rule.

R.