Stock Crankshaft?
The stock crank would most likely take it, but not so sure about the longevity of the rest of the rotating assembly (rod bolts, pistons, etc.). The crank will most likely be the last thing to fail on a 250+ shot.
I know a guy running a 250 shot on a completely stock lt1! He is running a stand alone fuel system with it and a spot on tune. It has handled it 30+ runs. It ran 11.7 118. I dont think it picked up much at all going from the 200 to 250 on the stock motor.
Other factors would come into play such as RPM, current power output, cylinder pressure, etc. I haven't done it so I won't say you can do it and be fine, but there has been big power made on stock cranks. They are going to be much more sensitive to any detonation than any good 4340 crank though.
