I used to run a Cheater NOS system on my 250.
http://www.jegs.com/p/NOS/NOS-Cheater-Ni...CFYZaMgodr1IAKACrazy fast I might add, w/the smallest jets the kit came with.
150-175 HP for smallest jets the kit came with.
Minimum cubic inch is supposed to be 350 C.I., I was just shy of 100 C.I..
I just used smaller jets than what the kit came with.
I would not recommend this kit for you especially if you have cast pistons.
Use a dedicated fuel system for your Nitrous.
MBHD