I'm running an LS1, cammed with 45# injectors. Mafless . I had 750 almost trouble free miles, (the car bucks at slow speeds.) I took it to Roebling Road raceway for some track time( 2.2Mi road course) It ran fine for the first 3 20 minute sessions. It then would hesitate badly off of left hand corners. The tanks were 3/4 full, but it felt like a fuel pick up problem, so I topped off. The problem got worse to the point I parked it. At the end of the day I droave it 60 milles home w/o incident. Two weeks later ( and 15 deg higher ambient) I drove it to Hutchinson Island for some parade laps behind the pace car. The problem was even worse. The throttle will not pick up out of the turns. It Finally quit altogether on the way home. Feels just like vapor lock to me. Any thoughts on where I should be looking?