Oh sh!t I didn't know the tracks were open yet...now I gotta finish my exhaust setup ASAP!!
I guess oil temps and DA can account for the difference. But 6mph is still a HUGE difference. I didn't realize the Z's were that picky about oil temps. On a few 80 degree days I trapped 100.x so I can imagine seeing 103+ with a good DA. After my setup change I'm hoping for 104 (so I can somewhat keep up with my buddy with a 370)
Btw...powershifting definitely helps, but I don't think you'd see ~2mph change in trap. I could be wrong though.