I agree with dubster...people talk so much sh*t about Nitrous , and they dont know anything about it.......I know a mechanic who has installed NOS in hundreds of cars within the past few years, and he never ONCE had a blown engine reported to him.......The key is to make sure that the person installing it knows what he is doing. BY the way, thie mechanic ( he has a 740 hp supra single turbo, by the way , with NOS), told me that the amount of shot you can run depends on how much stock hp your engine comes with... You can run Nitrous shot up to 50 % of your stock hp. For example, if you are running 150 hp at the flywheel stock, you can use up to 75 shot without changing internals. Likewise, a 200 hp stock car can run up to 100 shot on stock internals.