the car make feel like it just keeps going, but your not making any more power than you were at 7800 rpm, all your really doing is delaying a faster speed by not shifting into the next highest gear which makes your speed faster, how high were you revving your ls?.....and i dont think the nitrous kit made you bend a valve, unless you were overevving, missing gears at high rpm, at the same time, nitrous will definitely melt some shit if its not tuned right, if it burns to fast because of too far advanced timing or lower octane or if your simply not getting enough fuel to cool the chamber............