How much nitrous for a stock piston?
I have ran it on a higher compression engine with cast pistons.
1. Engine needs to be in "Known" to be good condition.
2. You can NEVER have detonation.
3. You can NEVER go lean.
If you can guarantee the three above you should be ok until the tranny or rear end blows.
With nitrous if you go lean or detonate it will "F" things up so fast you will never shut it down in time to save anything.