It's hard to beat the os speed engine. It's not just about raw horsepower ts about how it's put to use. There are several engines that have more raw power than the speed but they are not as smooth and they do not get the mileage that the speed does. I had a powerhouse modded toro that definatly out does the speed in hp but it was like comparing a balls out corvette against a ferrari. Depends on what you like and what your style is.