RENNtech Carbon Fiber Flat Top Airbox for M113/112 EnginesRENNtech Carbon Fiber Flat Top Air Box for M113 112 Mercedes Engines RENNtech Carbon fiber air box for the Mercedes V8 engine (M113 112). Our full carbon fiber airbox is more than just an impressive under the hood showpiece. By allowing a greater volume of intake charge air; our carbon airbox upgrade allows for greater horsepower and torque across the entire RPM range. The result is an additional 10 HP and 10 Lb ft with increased throttle response and