I have a 92 hatch with b18c1 and a 100shot zex. I had been running 55, then steped up to 75, but the main thing I can tell you is get some cam gears, get your timing retarded right, and MAKE SURE THAT YOUR FUEL SIDE OF THE TIMING IS RIGHT. Use a timing gun, or take it to a shop, because you will damage your engine with out enough fuel, or if you run on stock timing. I tried 75 a few times without any timing adjustments and had no problems, but its not suggested. Get some NGK cold plugs(like $5-6each)or zex plugs, and just have fun with it. Nitrous is a great upgrade for a car, just as long as your getting enough fuel.