A 350hp shot of nitrous is still absolutely massive for a street car. I though about putting a real small shot it my car (50~) but decided against it, I would probably not ever use it and it wrecks a manifold and looks ugly on the engine. I can't even express how spectacularly large a 600hp shot would be; I've found one online and the car made more than 1300hp. If the engine made 650 hp without it, the most I would consider going is 200 but some facts seem fishy here, those numbers are outrageous.