Serrated/Helix Design: The serrated/helix design creates air turbulence in the intake manifold. This turbulence increases the air pressure in the combustion chamber resulting in increased horsepower, torque and improved throttle response. The Serrated/Helix combination design also reduces intake whistle that occurs with other helix only designs. 6061-T6 Billet Aluminum Construction: All Silver Bullet Throttle Body Spacers are precision machined from 6061-T6 billet aluminum for lightweight, high strength and perfect fit and finish. Installation Is A Snap: This Silver Bullet throttle body spacer uses all factory mounting locations and a gasket providing stability and a hassle-free installation. This part will not work with an aftermarket intake system. Fitment Note: This item will only fit models equipped with factory intake