I have heard from alot of guys that some plugs don't work well for turbo cars (i.e. spilt fire,...). If you can I would use a higher octane gas. None of the guys up here (Canada) will use anything but 94 octane unless it is an emergency and thats even on daily drivers running low boost. I think 12psi is a little high for daily driving on a stock motor. I think 8psi might be a little safer unless your at the track. Just my 0.02