Depends on what you are doing for the tune and what heads you are running, converter, etc, but I would say somewhere in between there with the stock heads. Give me a week as I am about to select a cam for my friends 6.0 that we are adding long tubes and a tune to and I want to make sure I don't select one that will create a piston/valve issue with the stock 6.0 heads. It will likely require a valve spring swap though.


. Started fixing the last minute throw this on just to have it before a run.