I'd put my Os 1.08 2 stroke up aganst any 1.20 4 stroke for hp, I have a 1.20 magnum 4 stroke, it doesnt have the power or the rpm to match the 1.08, this engine can spin an 18X6 prop although i use a 16X6 , my 1.20 is rated for 12,000 rpm, the 1.08 16,000 rpm @ 3 hp (14x6)..