Well...I had half a tank of 100 unleaded in my baby the last few weeks and noticed my boost was only going to 20 lbs...I thought maybe it was just the hot weather doing that...but...I went out again tonight with a half tank of 112 octane leaded and the boost is back up to 22 lbs! ??? What gives with that...I know Nitrous Pete always told me with my tune to get the most out of it to run the 112....seems like it might have something to do with boost? Not sure....but its the only thing I changed and the air tonight isnt that great either...so for now on...112 all the time.