Engine Valve train timing plays a very important role in determining an engines power band. CAD designed & CNC machined from billet aluminum. Ralco RZ adjustable cam gear allow for precise tuning of valve timing. Clearly marked with 20 degrees of advance and retard, the slotted type allows for easy adjustment. The lightweight construction and hard-anodized outer ring reduce wear. If you are looking for the best gears on the market order a Ralco RZ Cam gear.