doglogan

I have a 350 in my 84 that is mildly modified and has a 650 Thunder AVS on it. It hesitates/stumbles on hard acceleration from 3500rpms up, no stumble on initial acceleration. If I accelerate at part throttle it doesn't do it, even up to 5500.
I thought it might be starving for fuel, so I set up a fuel gauge where I could watch it and it stays at 7psi. I adjusted the float level to Edelbrocks specs and adjusted the accelerator pump linkage to the position closest to the carb with no change. I also tried adjusting the jets/rods up and down and adjusting the secondary flaps.
Does anybody have any suggestions?

Night rider327

iTrader: (13)

1st 7 psi is too much fuel pressure. The edelbrock carbs do not like more than 5.5 psi really.

The orange step up springs are too weak for most mild combos, a swap to the plane silver ones cures most probs many folks have

doglogan

I will swap the springs and put a regulator on it tomorrow and see what happens, thanks.

Night rider327

iTrader: (13)

Your welcome... Oh what did you set the floats too? I know a while back edelbrock had the wrong specs listed in the manuals, have not looked at a new one to see if they fixed it or not.

Floats should be 7/16" at rest and 15/16" to 1" drop measured on both with air horn gasket in place and readings took at very front tip of the float.

I rebuild alot of the edelbrock carbs and have a couple of small steel rods in the correct dia. made up for fast, easy float checking and setting. You can also use a 7/16" drill bit to check at rest settings.

I find having a dowel or rod to slip under the float much easier than trying to hold a tape measure or steel rule up to them.

Also sounds like it could be a lean bog and you need bigger sec. jets, more pump shot or bigger nozzles, but I would hold off on that untill you try the step up springs

doglogan

I changed the springs and added a regulator, it's pretty much the same. I also tried changing to the #7 calibration on the chart, 3 stages rich on power mode and 2 stages rich on cruise and it seemed to get worse.
7/16 and 15/16 were the specs I used when I set the floats, I think I got it from the dvd that came with the carb.
Are the jets in the bottom of the float bowls the secondary jets or is there another set of jets? This is the first edelbrock I've had.

Night rider327

iTrader: (13)

Bottom back of float bowls are the sec. jets. Bottom center is the prime. jets

doglogan

Ok, would you start with bigger secondary jets?

Damon

Doesn't the secondary air valve on an AVS carb have an tension adjustment spring? I think that's why they call them the AVS.

Have you tried playing with that, given you don't have any problems unless you lay all the way into it (begin using the secondaries)?

doglogan

Yeah I tightened up the spring past the factory spec and it helped. I tightened it more and it made it worse so I set it where it was good. I haven't changed the secondary jets yet, I'm hoping to get a chance this weekend.