Thanks, for the info, truckracer. I couldn't remember which number it was, figured somone would set me straight. If it is 45, it's a 3.7 and will never turn a 24X10 in the range it should, maybe a 22X10 would be more to it's liking. Actually, any engine that doesn't run in the 7,000 rpm range isn't propped in it's power range, that's my opinion.