Sorry for the delay in replying to this but one or two things have rather pushed racing into the background. When i stripped the motor it had shattered the wrist pin and the piston and squish band showed evidence of severe detonation. Having a look at the rest of the boat revealed that the bendy tube stinger extension (needed to get the outlet out of the transom) had split and collapsed! Motor then rebuilt with new button and .015 clearance. Started ok and is now throttling well but is now no longer in the boat! I had been running it in a Challenger 43 on a gearbox in our (BMPRS) AA class but have now put in an OPS 45, also on a gearbox, for A class racing. The Nova Rossi is going in a Pursuit for AA. I've got the hull and hardware but am in the process of building a new workshop so progress is painfully slow and frustration painfully high!
Cheers
Bob