ok im buying a 6.0 Lq4 from a friend of mine including the 4l80e tranny, wiring harness, alt, computer, and basically everything i need. One, will i have to change my drivetrain? second, is the lq4's compression lower than the lq9's? well with the 6.0 full exhaust,cam,and 100 shot wet what do yall think i will do vs. a stock Trans am?( not from the highway,probably a 40 roll)

 

If you are 2 wheel drive the only thing you will need to do is get a different yolk on the drive shaft and the driveshaft may need to be shortened a little. And you will need to modify the cross member. The c.r. is lower on the lq4. You should be quicker than a stock f-dody if you can get traction.

 

The 80E is longer than the 60E. There are several parts that need to be changed to convert from a 60E to an 80E, check out http://speed-eng.com/store/index.php?cPath=23_940_1409


The LQ4 is 9.4:1 and the LQ9 is 10.1:1