F1 Racing Lightweight Chromoly Flywheel 81043FX8-HT Ultra heavy-duty and weighs only 16.4 lbs (stock flywheel weighs 25 lbs) Made from 4140 forged chromoly steel Incorporate special design features to enhance the airflow for improved clutch cooling Ring gear teeth are milled onto the flywheel unlike an aluminum flywheel where the ring gear is pressed onto the flywheel which has the possibility of separating from the flywheel. Designed to reduce weight for better engine response