Aiming at the problem of camshaft torsional oscillation caused by the torque of the engine camshaft spring. this paper carries out the research on the compensation of the elliptical pulley timing system for the torsional oscillation of the camshaft. In the quasi-static state. a dual overhead gasoline engine drive system model is established. https://cosmeticssquadets.shop/product-category/face-serum/