My motor currently has a stock bottom end and stock dished pistons, it also has a fresh rebuild with new bearings all the way around (if that matters).

I was wondering if it would be able to handle a 75 shot of nitrous semi reliably, or would I just be waiting to melt a piston or bend a rod?

compression is probably around 9.5:1

Any input would be helpful.

 

if it's the 350 in your sig, 75 would be a piece of cake. If properly applied 150-180 should not be a problem.