There is a lot of threads on pump gas. What kind of boost and timming is safe on 100 octane. I never run pump gas in my car. I'm presently running 19#'s on a 3.4 and 17 timming. I ran a return style fuel system with dual intank walbros so I have plenty of fuel. Even though my tune is mild I still make 649hp and 619 tq. It just never seems to be enough!