I went to Dick Millers Olds/Buick/Cadillac race in Norwalk zohio this morning. First pass was ok, next pass I staged the car, lightly torqued up the engine to about 1300( (just enough to take all the slack out of the driveline, just like I always do on the track) last yellow I swap feet. The car launches normally for a split second, front end comes back down and the engine screams. I thought for sure I broke a driveshaft or U-Joint. The is no carnage, I start the car and it goes right back into gear. Hmm?! I thought maybe I bumped the shifter into nuetral?? Next pass, same thing!! I looked closely at the driveline, I drive the car hard on the street, everything looked at felt normal. I attempted on more pass with the same results. At that point I decided to put it back on the trailer. This is a 400 trans with a modified factory valve body, dual feed, deep pan, fluid level is correct and clean, I’m scratching my head. Is there any possibility the low roller clutch could be slipping under full throttle during high traction conditions? Other ideas or things I should look for during the autopsy??