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.

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