Just checked my tacho reading again today with both props (both Master Airscrew)

Im getting 11500 with the 12x8 and about 10500 with the 13x8, both static on the ground. The 13x8 seemed to give a lot more pull on the ground, am going to give it a fly with the 13x8 tommorrow if the weather is good.

Im using the TT Rear Bear custom muffler too, this has given me about 500-800 more rpm over the stock muffler on the test stand anyway. Is louder though, but I think it sounds good.

10% Nitro / 20% Coolpower home brew, and only about 16 deg cel today.

Cheers