Nuke Performance Adjustable Aluminum Cam Pulley for BMW M20 — precision engineered in Sweden and trusted by world-leading BMW tuners worldwide. CNC-machined 6082 aluminum for strength and reduced rotational mass Hard anodized outer gear for minimum wear over time Adjustable +/- 11 degrees for precise cam timing Unique bolt washers that optimize tension during racing Abrasion-resistant Helicoil inserts Compatible with naturally aspirated and forced induction setups Fine-tune your valve timing for maximum performance gains — advancing timing clockwise, retarding counter-clockwise. Improves power, torque, and overall engine efficiency. The most widely used adjustable cam pulley for the classic BMW M20 engine. Replaces BMW part number 11311714988.