A Stock car breaking a driveshaft... what the hell.
I have done consistent low 12's with a stock clutch.. brand new but still stock.
Hey even my brothers GF has done consistent low 12's in his GTR and a stock clutch..
Say 12-13psi, on stock 225/50/16's and a mid rpm range clutch drop (depends on track) easy low 12's every time.
You have to know how to change gears fast though, changing like an 80yr old woman will not give you fast times.