What flywheel did you use? I have two T56 transmissions; one will go behind a Lt1 with stock clutch & flywheel and the second one is setup in my '40' Ford behind an early 350 sbc with a pricey flywheel from Centerforce #700107. If you have the incorrect flywheel the balance will be messed up. Hope this helps. I find it hard to believe that it is something internal to the trans if it was a good trans in the 94 Camaro before.