Hello Ron, that was my mistake, I meant 85mm. I need something at least 85mm with the gudgeon height to suit an M20 crank, do you know what might suit? Thanks, Pete
AH! The piston I used was from the "long Conrod" B33 engine. But it only works with an M21 crank and gives 633cc. I expect Ian will be along with information regarding a bigger piston for a standard M20. Ron