I always run 93 octane even though I could probably get away with less since my heads are only 69cc. It seems like I can hear my cam alot more here lately too. I don't know if it's because I ported my TB or it's just getting a miss . So are you gonna wait to get a retune before you take it to the strip? Hey BTW mark it down on your calender Aug. 24 is Summers Last Blast in Vernon Tx. and after the cruise is over at 10:00, WRP has heads up drag racing. It's usually pretty badass. A lot of bad to the bone cars come out of the woodwork. I think it would be cool to get alot of us LS1Truck guys to show up and crash the party.