How many steps colder plugs should I get for my 7psi'd kit? It's only putting out around 160-170whp but still know colder plugs would still help out with the added boost. Help. I had one step last time I had my car boost but would 2 step colder plugs be too much? This is on a y7 with a small IHI snail and I really never see going over 10psi anytime soon.