I always used NGKs in my 451, my compression was 9.73 with iron heads, i used the -6s NA, ran -7s with a 100 shot, seeing you have 11.5 compression, i would run -8 NA & -9 on the bottle, tighten up the gap to .030", pull timing accordingly & make sure you have good fuel supply, wouldn't hurt running a dedicated fuel system for the nitrous, get you a 2 gal. fuel cell & mount it on the pass side radiator support along with a pump & reg., running relays is also a must, you'll definitly need raceing fuel, i would run 110-112 in it, if your going to run that much nitrous, you need to do your homework, otherwize "kaboom", i hope your engine is built to handle this much shot too, if it were me, i would start off with 100 shot & go up from there, i love nitrous, its not as deadly to use IF you pay attention to whats going on EVERY time you use it, allways read your plugs, but the more you shoot through it, your stretching the envelope.
