EVE200-129 / 200-129 - Application Notes * Please Note: 2004 Duramax: VIN eighth digit "1", fits LB7 engine only. Designed specifically for the Chevy Duramax 6.6L Turbo Diesel. This system produces 14 horsepower over the stock air-box unit! Our exclusive Filter Adapter tremendously improves airflow directly into the intake system. Another feature is our CAD (Cool Air Dam), which helps to isolate hot air away from the filter and provides a denser airflow charge.