Brett,

Can you recommend a staring point for me to try the RoJett 61BB in my  Thundergazer?

I have B.E. 13 and 12.5 3 blade props flat back.

The Thundergazer is all take apart with split foam wings and it came out on the  heavy side.

The only odd thing I noticed about my RJ61BB engine is that it needs to turn about 84o for the piston to pass lower line of the exhaust port and appears back again. Shouldn't the lower line of the exhaust port match with the piston crown at BDC?

Martin