I've recently replaced the intake and carb on my 1970 440 and have an issue I'd like some real world direction on before I tear into the carb.
I had an Edelbrock performer RPM intake and a Holley 850 Double pumper on the car previously. The car ran well, and was great leaving a stoplight either in my neighborhood at low speeds or when moving off the line a little quicker This combo was really too tall for the stock hood and I wanted a more stock appearing engine compartment.
I swaped in a 1971 square bore iron 440 intake and an Edelbrock #1411 750 cfm vac secondary carb. I'm OK with the overall performance of this combo as this car is a driver and I'm willing to trade maximum performance for street manners.
The issue I have is an off idle stumble at light throttle; I need to give the car much more throttle to leave a stop smoothly than I did with the Holley. If I rev it up and slip the clutch more, it works great, but at light throttle it stumbles/bogs.
I've been reading on the internet and this seems to be a fairly common issue with this carb on larger displacement engines.
Has anyone had real experience with these, I just wanted a reality check before I go tearing into this carb and spend a bunch of money and time for marginal results!
Thanks!
Scott

Try a different hole for the accelerator pump rod, if it gets better then try the next hole, if not quite ther then bend that little connecting link a little bit and I bet your problem is solved

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.

Depending on your engine componits, your engine may require more fuel...so you may have to rejet it.

Is it a new carb?

Might just be a weak accel pump not shootng out fuel right away.

Look down in the carb and move the throttle, see if fuel comes out right away.

pump rod is in the closest hole to the pivot(most sroke) I'm thinking of going to the .043 shooters vs the .035 that is on there now, I've also been told to drill out the idle tubes a few thousands of an inch, and to get the tuning (rods and springs) kit. I was just wondering if anyone has tried this? I don't want to spend $100 on carb tuning accessories for trial and error.

Put the money in another carb. A Holley or any of the other Eddy offerings is going to work out better.

You can take this current carb apart and look for crap left in it, some people have said they had junk in their brand new carb.

You might need stiffer springs, it may be sucking the rods down and blocking the jets for a sec. Would be nice to try somebody elses springs in it before you drop the money on the strip kit.

I have been through this personally with a couple of Eddy 750's and I have a solution that Does Work!

1) Verify that your floats are set properly

2) Try different springs for a quicker opening of the needle.

3) Verify that your accelerator/plunger is good(replace if any doubt)

4) Adjust the linkage that operates the accelerator; There's 3 settings, I believe the arm should be in the top hole.

5) Finally, the thing that most guys won't try: Remove the Primary Squirters and drill them out very, very slightly(get some tiny, tiny drill bits). Don't be afraid to try it.

The last one is what did it for me.

Let us know how you make out.

Be EXTRA sure you have tried EVERYTHING else before you drill or modify ANYTHING. The fastest way to start chasing your tail before you find the real problem is to start modifying componants.

yep. Start small, it don't take much out initially and be sure to follow/drill straight thru. (No coke bottleing at the end)

Instantly noticable improvement.

You made it clear your wishes were to stay stock looking and have more clearance. You Were Clear on this point. Yet the usual Anti-Eddy/holley-rules crowd had to ignore your preferences.

I love Moparts, don't you?

If he wants it to look stock he needs to find a Carter AVS or second choice would be the Eddy AVS.

What was that about ignoring his wishes of looking stock???

Get the tuning kit for that carb and follow the booklet instructions that came with that carb and you should be able to easily fix your off idle stumble problem. These are some of the easiest carbs I know of to tune, and the booklet makes it a no brainer. Edelbrock did their homework. For your application you shouldn't have to modify anything on the carb to get it to work well. Per many good comments on this thread, make sure the carb is healthy to start with - good pump diaphram, floats set properly, etc, then just make changes to the rods, springs, jets, pump rod, per the booklet ( calibration reference chart )and you should be good to go.

Thanks for the feedback,

I guess I should clarify, I want a stock appearing engine compartment with the stock air cleaner and coil location, those were not options when I had a dual inlet holley and tall intake.

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"Pretty, but can it fight." Stock appearing ? - "CAT" on the side of your battery aint workin.

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You have to understand this car is a driver that is still in the process of becoming a complete car from the abandon project in boxes and pieces that it was when I purchased it a few years ago, I'm just trying to do this one step at a time, and I already had the battery!

Thanks,
I looks better in pictures than it does up close. If I was worried about perfection I'd just build a big model and keep it on shelf, this car gets driven! Thus my desire for a smooth operating carb!

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.