The Silver Bullet throttle body spacer is constructed from precision machined T-6061 billet aluminum and is designed using a serrated/helix design that creates turbulence in the air flow at the point just prior entry into the engine optimizing the combustion cycle. This turbulence helps the air/fuel charge burn completely providing increased horsepower, torque and improved throttle response. In recent testing this spacer produced 6 Horsepower and 13 lbs. x ft. of torque. This spacer was dynoed with a aFe OER air filter and dynamic air scoop. This Also Fits: BMW 135i (E82/88) 11-13 L6-3.0L (turbo) N55, BMW M135i/ix (F20/21) 12-15 L6-3.0L (turbo) N55, BMW M235i (F22) 14-15 L6-3.0L (turbo) N55, BMW 335ix (E90/92) 11-13 L6-3.0L (turbo) N55, BMW 335ix (F30) 12-15 L6-3.0L (turbo) N55, BMW 335i/ix (F31/34) 13-15 L6-3.0L (turbo) N55, BMW 435i/ix (F32/33/36) 14-15 L6-3.0L (turbo) N55, BMW X1 35ix (E84) 13-15 L6-3.0L (turbo) N55