RE: 5HP!!!???!??!?!?
its really hard to compair for instance take a 300hp sports car like supra or wrx and hook it up to a 20,000 lb. trailor next to a desiel like a one ton truck hooked to another identical trailor. now let them pull the load. what do you think the outcome will be?
being able to do the work under a load is mostly the engines availible torque.