Both Kohler and Kawasaki claim that there is no change in HP or torque between vertical and horizontal shaft engines. HP is as stated on either and must be certified by outside testing agencies before the rating can be sold as such. The CC displacement for identical HP engines is the same. The different designs are produced so that they can be utilized in different mounting applications providing clutch and pulley alignment for more compact applications. That's all! :hammerhead:Vertical shaft engines, pound for pound, produce less power than horizontal shaft engines.