I just wrapped the head and heat cycled it two tanks on the starter box and then another two tanks putzing around my driveway. After that I ran another two tanks pretty rich at the Plex and then started to tune for power. This engine likes to run really cool so tune by power and exhaust smoke more than by temp. Opening week at the Plex the hottest my engine got was 210, steveja pulled his gotech off at 280 when I was temping mine I also put an O.S. P3 in mine after break-in, seems to smooth out the idle compared to the cold plug that comes with the GRP.