602 stumbling on throttle

[zlssefi]

Im having an issue with my 602 guys, coming out of the corners on a 1/2 mile high banked track the car stumbles, pops and hesitates when i get back on the throttle to pass cars. The carb and engine were new this year and were dynoed before i put them in the car. My timing is at 32 degrees and im running 73 75 for jets on d-98 fuel. Any idea what might be causing this issue?

[jtrent64]

what carb are you running?

[zlssefi]

i have a 80541-1 holley 650

[jtrent64]

I had a similar problem with the Holley 0-76650, switch from 93 Oct. pump gas to 110 race fuel, and swapped out the front float valve. Runs great now. I think it was more a gas issue than the float valve for me.

[Matt49]

It sounds like starving and surging. Make sure you don't have your float levels too low.
Run the engine, shut it off, and pull the site plugs on the side of the bowls. The fuel should be right at the bottom of the holes or just barely drip out. If you get too low, starving and surging can be a big problem especially on circle track applications.

[zlssefi]

I will check float levels for sure, do you turn the nut clockwise or counter clockwise to raise the floats?

[Matt49]

I will check float levels for sure, do you turn the nut clockwise or counter clockwise to raise the floats?

Clockwise lowers the float level and counter-clockwise raises.

http://www.youtube.com/watch?v=ge-mIk6nEYQ

[zlssefi]

The floats all checked out ok, the idle mixture screws...3 were 1 turn out, one was 1 1/2 turns out, would that mean anything? Also, i think the real problem may be the timing. I found the distributor clamp broken and the distributor was moving whereever it felt like going.....oops!

[dukeyyyyy]

im having the exact same problem with mine It completely kills me on starts and restarts. I've adjusted the accelerator pump arms a little and it seemed to help some. If anyone figures it out let me know!