Ran in auto-x last sunday. have a stock 98 ls1 swap with 4l60e and early 4th gen rear with 3.23 gears. I am running in FS because it is a local event and the only other third gen is a 1le car with konis. Currently the car seem to be very tail happy and with auto if it kicks to first gear it equals an automatic wheel spin. Tires are old worn out 710's . Just wondering if anybody can suggest on what can i do to make it little less tail happy and stop the massive body roll.
results:
final
raw
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anti roll bars, different suspension, springs

 

Try swapping in a smaller rear sway bar from a base model camaro or firebird. that should keep the tail from stepping out. poly bushings and good shocks/struts help a lot.

 

looks good. what do you have for suspension now?

 

suspension is stock ws6, new sway bar endlinks upfront and subframe connectors. Actually in the rear i am currently using a fourth gen sway bar, if it is larger than my stock one i will try putting the stock one back on before next auto-x.

 

Im not sure the diamater of the 4thgen rear bars, but your stock WS6 rear bar should be 24mm, which is the biggest rear bar you could get from 82-92. I would hit up a junkyard with a caliper that measures mm. the rear bars vary in sizes from 19mm, 21mm ,23mm and 24mm. the bigger the rear bar the more the rear will step out from my experience. if you can snag a couple rear bars from the boneyard in different smaller sizes, you can swap them on easily and figure out which bar makes your car handle the way you like for very cheap. I like the 24mm bar but i like to steer around corners with the throttle, and have about half the power you have lol. Very nice Trans AM!

 

it appears that the fourth gen bar is actually smaller. Went to another auto-x even yesterday and got few videos. Need a driver mod.
http://www.youtube.com/watch?v=L0VREVL4Dl8
http://www.youtube.com/watch?v=Z6skE5sBnR0