My G35 coupe has a custom single turbo. My friend drove cuz I drank a little too much. But he downshifted and bounce off redline, then upshifted and the car just died and didnt restart. I thought it might be a bent rod, but no loud noise. and It just clicks when you try and start it. Somebody else said it might be bent valves and head gasket. The shop I use said they tried to turn the motor over by hand, but I dont think they did b/c my turbo kit sits between the motor and core support. If you have any advice or ideas please let me know. that would be great thank you