Dave, your numbers are very good! i obtained lowers numbers because i dont use nitro in my fuel (80/20). The last measurement i made was 12.200 with a wooden prop, so your numbers are very nice. Dont forget that this muffler is very restrictive. this motor will last you "forever"if you use a nice fuel like this you are using (all castor)
nice flying


AHHH Dave, if you are using the APC props they are superb, but be careful to round its tips. Some time ago i cut my righ hand deeply with one of these