It doesn't matter too much with CR. I have 9.9:1 in my B16 (compared to 10.2 from the factory) and I boost to 12 psi daily. It's been 11K+ since I built it with forged internals. Just use good parts and get a great tune and use 93 octane. But it's going to be a bitch when it comes to emissions unless you live outside the metro area.