the etec H.O pushes the 10% margin on the rated horse power. so say its a 150 H.O in terms it really is about 165hp the push the boundaries of the 10%. this is from what i have read other people can correct me if im wrong. the 10% margin works for every outboard apparently the 150 yamaha is actually 162hp, and the suzuki 140 is really only about 127hp.