I'm digging up this old thread because there doesn't seem to be anything newer on the subject. My car bucks like a SOB at any speed if I'm on a flat road and try to leave it in gear, and I have to listen to the clack-clackclack-smack-clank of the play in the drivetrain. What fun.
But I feel better after reading here that it's common. My guess was that it was a combination of a 230/245 cam, Spec stage 4, and somebody setting up the rear end with too much play. But I thought mostly the rear end because, man, it's bad. Unless I have my foot on the gas, or the engine slowing the car like when going down a hill in gear, it's clack-clank-clank. I have to disengage the clutch about four times driving out of the gas station. But somebody who knows what they're doing took a look at turning the driveshaft and said it doesn't have an excessive amount of play, so I guess it's all the other factors.

 

My car did this with just a Hotcam for 50,000+ miles. It was tuned and everything, but extremely light throttle(cruising at 30-35 MPH in 4th) would cause it to buck. I just lived with it, but with your cam I'm sure it's much worse. I would think a lot of that could be taken care of with a better tune, but I never pursued it. I have since installed an A4, and now I only feel it with the converter locked at 35 MPH.

 

After 1 year, nothing is changed

Now I'm ordering a small cam sround 210 durations. Yeah yeah I know after that I will lose a couple of HP, but I'm thinking to go with supercharger.

I'm tired of dealing with, Bad MPG, Bad Gas Smell, Bucking, Shaking, Surging .....

 

I hear you, absolutely. I think a big cam is the worst way to get power. The thumping tough sound is cool, but nothing else is going to kill driveability and mileage like a big cam. Big heads, no problem; exhaust, no problem; intake, etc. But put a cam in and there goes the bottom end, driveability and mileage. My supercharged '96 396 is a dog until about 2300 where it's about equal to my old '94 I gave away and my stock 350 '99 Corvette. Below about 2800 the stock Corvette and 220/226 cammed 94 have a lot more pull. I don't know much about cams for FI, but I know a lot of the Buicks use the stock cam for fairly serious applications. I bought the '96 a few months ago and I'm tired of pouring time money and grief into it; but if I wasn't, I would be thinking about changing the cam to something smaller.