Fraxum

iTrader: (2)

I have a stock LT1 and when my original transmission was destroyed by a truck trailerball mount in the middle of the road I had a local transmission shop (run by a performace oriented sort of guy) replace it with a '93 M6. At the same time I had him install a Spec2 clutch (lightweight)and Spec steel flywheel.

Boy this clutch really chatters and the throw out is really noisy. But also I get a noticeable vibration around 80.

But now I realize if I just rev the engine sitting still I feel the bad vibes. Which is why I posted here. Clutch setup or something else?

I remember suggestions for this but can't find the thread.

zlover129

iTrader: (10)

flywheel is a possiblity, even new ones should be balanced

tspence45

iTrader: (30)

I'd say flywheel most likely. I'm sorta having the same problem, just not so much when I sit there and rev it. It gets real bad up top. I was running a T/A on the highway the other day, and it started vibrating up top pretty bad, and when I let off I could smell clutch a little bit. Oh well, I'm considering getting a better clutch/flywheel setup anyways. The bad vibration you're experiencing up top, is also caused a little by the steel driveshaft. That's why a lot of LT1 guys swap them out for the LS1 aluminum DS.

Fraxum

iTrader: (2)

Yes, I have an LS1 driveshaft but have not put it in yet. It is an all around good move unless you are making big power. I thought that was what it was, but it vibrates pretty good sitting still at 4K. I did not know a flywheel would have to be balanced. I bought the Spec one thinking it would be a little lighter than stock even though it is steel. I guess I better look around to see how to fix. It's a little cold right now to be dropping the trans.