I'm not sure where Justin has them set. I just shut up and say work your magic. The guy that has the dyno is a friend of Justin's also so he can let him know where everything is. I know I haven't lost any mileage with the blower. Based on Justin's recommendation I just installed NGK tr55 plugs at 0.035. I haven't data logged yet, but seat of the pants and visually watching the exhaust I think we are very close. It seems more responsive. It was time for plugs anyway.