Boost gauge is accurate, the one in my car and the one that the dyno company were dead on. Literally what you see in my SIG is all that I have done to the car, nothing else. It's a pretty fun ride at that the whp that it's sitting at right now. All I can say is that E85 loves timing from my experiences and of course requires a healthy fuel system. Walbro 255 pump, re-wire, and 60's were absolutely necessary.