Racing Cam Pulley Adjustable Gear Toyota Corolla 4AG 20V Blacktop Silvertop FEATURES Racing cam pulleys allow precise adjustment of camshaft timing. For added accuracy and longevity, the timing marks are machined into the metal, not painted on or silk screened. The cam pulleys also feature the most accurate timing adjustment system on the market. They are constructed from 7075 aluminum for optimum strength and light weight. High Accuracy Differing from conventional sintered pulleys (one piece),this adjustable cam pulley is made in two pieces. This enables the adjustment in the valve timing to be carried out. Since vernier type graduations are used, the adjustment can be carried to 1 deg of the crank angle (0.5 deg of the cam angle) in order to achieve maximum results. Super Light Weight Duralumin A-7075 is used for both its lightness and high rigidity in both the inner plate and the cam pulley. So implementing an improved design and the employment of Duralumin a 35% weight reduction is achieved. And not only is the overall weight reduced but also a reduction in inertia, leading to an improvement in engine response. High RigidityWith employing Duralumin A-7075 in both sections of the pulley, the overall rigidity is improved. So whether you are using a standard camshaft or a high performance camshaft, valve timing accuracy is improved. The two pieces of the cam pulley are then anodized helping to prevent the lock bolts from sinking, along with surface treatments (precious metals) to help reduce cam belt wear.Intake Exhaust ( 1 Pairs Cam Gear )