Also begin saving your pennies and dimes for a different carb. At least half the 750 Edelbrocks out there have a pretty incurable stumble. They are famous for this.

When the inevitable post comes along after me saying "I run 10s with my Edelbrock 750" you can sell yours to him. It never fails. During the time that I was buying carburetors from Ebay I noticed that the 750 Edelbrocks were selling for less.

R.

But when I stomp on the gas it goes completely flat/lean for a sec, then must get a burst ofgas and goes balls out..

I'm sure you've checked this but is the AP tip in immediate upon the slightest throttle movement? & of good duration and are you on ported for the vac can?

Here is what I did , it runs and there is no stumble off of idle , at all , this worked for me.

Drilled out the accelerator nozzles to .045 (went to .041 first)

Installed the .113 primary jets

Installed the .073 X .037 metering rods

Installed the stiffest metering springs

This is close to where I am at so I hope it runs once I finally get going.
Can you give a brief description of your motor specs/parts as it would help..

Have ANY of you ever tried drilling the idle feed tube, changing air bleed size? Or is it easier to give up and complain? People will change metering blocks, air bleeds, squirters, squirter cams in Holleys till they turn blue. Heaven forbid you try something on a Edelbrock besides squirters, springs, rods or jets. Think outside the box. If it's lean, richen it up. It's still just a carb. Is it a full race Holley, absolutely not. Can they be a decent carb, yes.
Doug

I have finally ended up with one of these notorious carbs, never had any problems with the 600 and 800's that a little tuning did not straighten out.... till now. I acquired a brand new 1411 for free. I put it on a mild 440, 240@50 cam, Holley SD intake and proceeded to tune. Big off line stumble, the distributor needed more initial and a curve anyway, so I bought the plate kit from FBO that allows you to limit total timing in the older MP dist, without having to play the braze up the slot and file game. This thing is great and this particular engine is very happy with 20* initial, 34 total, and using the vac advance adjusted to add 10 at idle on the full time vac port as recommended by FBO. Before I got the plate , I had tried the .043 squirter,HP orange(marine) acc pump plunger, and played with the jet metering rod combos until its infamous off line bog was almost gone, but not quite! Getting all of the timing issues squared away finished it off and made the car a joy to drive under all conditions but one. If you are at a complete stop and floor the throttle, it literally dies! You can hit the throttle briskly and smoke the tires, ease into the throttle and spin tires, but if you mat it, it dies! Pump is at max shot, passages are clear, and it will die every time if you mat it from a standing start, if you are already moving, no problem! it is like it is going massively lean. The floats are perfect, I am frustrated as the devil! I can put the tuned 1406 6oo cfm carb on it and it will come off the line sideways, same with my 800 performer, but that ****###@@ 750 has me stumped. It works great except that one situation. No bog in any other form of accelerating, just full bore from a standing start! Any ideas on this one??? Lee.

I didn't realize the NSS cars leave the line "OFF IDLE"

Thanx for clarifying that

LOL
Anyways

I tried drilling the idle tubes on my 1407 - Didn't work or help or change anything

On the street , daily driver , "OFF IDLE" the Edelbrock 800 series AVS is 1,0000 times better the carb

Many do. Mine will, but for reaction time I leave higher.
Doug

I have a 1407 I'll sell you that came off my hemi for $150. It"s in like new condition with all factory settings.

The same price I sold the other one to a friend who has it on his corvette.