Stoplight sputtering

[sccabrian]

I have a 72 with an 83 ( I think ) carburated motor in it. I have it running great considering it didn't run when I got it and I'd never tuned carbs before. The problem is that when I stop at a light for more than a minute or two, the car starts sputtering and bucking when I start to go. It usually clears up by the time I switch to third. This is particularly annoying at the track where I can consistantly run 18 - 21 second quarter miles. haha. Also, the front bank of spark plugs look to be a little gunky as if they were running rich, and the backs look a little white ( lean? ) even though the carbs are in sync and I tuned them together. I'm a little lost here, and any help would be greatly appreciated.

[dogma420]

One test that is really good that might fail even if you think they are sync'd is to cover one carb while running with your hand / towel. The motor should still run. Do this with the other carb, it should still run.

A lot of times, I'm completely dialed in (at least I think I am) and then I do that test...and it fails...

A great source for carb tuning is Z Therapy