Take this with a grain of salt, worked for me. A local tuner told me the 750 idle air bleeds are way too big and cause a bad hesitation. I pulled the top off the carb, and peened the air bleeds from .055 to .035. Car runs way better, much snappier off the line.

After. Careful you don't mangle the base surface while peening th e bleed.

Noted as I have an Eddy 750 in the works. the guy sold it to me for $25 as a used/rebuilder carb so it might be one of the bad ones

Looks like it may be possible to drill and tap for a replaceable bleed like some Holleys.

R.

thats the way I'm gonna do it if I have a problem

those carbs have two idle air bleeds and one idle jet. the air bleed at the top of the cluster can be drilled and tapped for a 6-32 holley type emulsion jet. the air bleed on the side of the cluster may not be as straight forward to modify. the idle jet on the 1407 i have is .037". generous enough. the air bleeds are .046" and .056". combined area for both air bleeds is in the ball park in relationship to the idle jet size. going from .055" to .035" for a bleed is a very, very big step. after messing with bleeds i've found that only a few thousandths can make noticeable differences. if the carb the OP has needed this kind of change then i'd be looking at why. the idle jets can get clogged or dirtied up which will cause the idle to go off lean. low engine vacuum and slow timing with a performance cam will screw up the idle circuts.

How do you know which is bad?

did edelbrock fix the issues with the newer ones?

(1) there's been alot of reports here on em & that no matter what was tried they still cant be made to run right & people were even speculating that it might be an assembly line glitch where some passages were drilled wrong but in all fairness some people have used em & been happy. For $25 I feel lucky & I am gonna go thru it from head to toe when I get around to it (I have a kit & a strip kit so I'm committed to a certain extent). (2) I dont know

Had mine since 88 with no issues.

i think the biggest problems with these carbs is the users lack of knowledge on how to tune them and possibly any other carb. it's rare that any aftermarket carb is a bolt on/no tuning success. these carbs may have some manufacturing issues but nothing that would prevent them from being good drivers. the 750's and 800's are stupid rich out of the box, but why should that be a problem not easy to overcome? they come with a manual explaining operation. do people read it or toss it? parts are readily available. i'm running two 600's on a ch28 and think they are more than a great pair. the factory avs's have emissions issues to overcome but once that's dealt with they are great drivers and performers.

The typical response when something does not work right and the user does not understand how it work is to criticize it. They may be adept with Holleys but do not understand that all carburetors do the same but they do it differently. If one takes the time (which they rarely do) to understand the "THEORY of Operation" the issue will generally troubleshoot itself. This applies to a lot of things other than carburetors.

well said.

From the photo, the fuel level looks a bit low in the fuel bowl too?

Your idea really hit the bull's-eye

Nothing more to add other then Agreed.

A little ignorant on carbs here, but what exactly does a smaller air bleed fix? I had a 750 Edelbrock and it was as you say, always had a bog on tip in. From what I recall the air bleed mixes air with the fuel and emulsifies it. To big an air bleed causes a mean condition? Wouldn't a bigger jet accomplish the same thing?

a large air bleed weakens the vacuum signal to the idle fuel supply; smaller bleed strengthens the vacuum signal to the idle jet.

i've found the bog in the larger carbs is related to too large of a squirter and too rich main metering. opposite of the "carb conventional wisdom".

In my case it was definitely lean bog, if I pumped it while it was stumbling it would catch and off we went (giving her accelerator pump shots). I had an Edelbrock 800 Thunder Series (AVS style) I swapped on and it was much happier (stock LC 440 with headers)

the 800 has a larger accelerator pump.

Also think of it like this. The larger the air bleed the more air in that circuit whether its an idle , main or high speed air bleed and the more air the leaner that circuit. And yes to a point in some circuits a larger jet can add fuel to run richer or a smaller air bleed can give less air and run richer. Thats one nice thing on the modern carbs with billet metering blocks that will have jets in many circuits as they usually have idle and main circuit air bleed jets and jets in the emulsion circuits , this idle restriction circuits , P/V channel circuits and so on. Its nice as you can really fine tune newer carbs much easier with the ability to just change bleed and fuel circuit jets. The older 850 I run only has main jets as I have to drill and modify it to do alot of tuning on it.
Even in the main jet circuits its nice having jets in the main high speed air bleeds as you can really fine tune as sometimes a small airbleed change will be enough to get the change needed where the main fuel jet change may be more then you want. Thats the nice feature of the 02 sensors of today which help in the fine tuning. It lets you try and see how much changes are made by the air bleeds or jets and many times if you have not worked with that carb you just have to make minor changes and see how much the circuit changes you are working with. I grew up doing it the old school way as we did not have the nice 02 systems they have today back in the 70's and we did most of our tuning by reading the plugs and track times. Ron