I would think 915's should satisfy FAST rules & if they in fact do they are a huge advantage in building a motor that will run on pump fuel... Beyond that I would build the 505 combo rather then the 493...17cc dish pistons, .010 below deck , .039 head gasket, 81cc chamber = 10.4 C/R
Beyond that I would build the 505 combo rather then the 493...17cc dish pistons, .010 below deck , .039 head gasket, 81cc chamber = 10.4 C/R