i said 1 + car.. it was a while ago, so i know i for surely gained at least 1 car.. dont' wanna say like 4 cars and not know for sure and get your hopes up. well probably gain 10-12 whp from the headswap. and with intake header exhaust probably.. 8-10.. how much does I/H/E gain you in the quarter? not enough.... so your looking at maybe like .3 -.5 second difference in the 1/4. and i think 3 cars is about 1 second.. so 1 car is like .3 better... i dunno tho.. JMO