aFe Silver Bullet Throttle Body Spacers TBS BMW 335i (N54) 07-11 135i/535i 08-10 L6-3.0L (tt)46 31002 Silver Bullet throttle body spacers create turbulence in the air flow just prior to entry into the engine increasing horsepower, torque and improving throttle response and fuel efficiency. Silver Bullet throttle body spacers are constructed out of durable 6061 T6 billet aluminum and use a unique serrated helix entry to create turbulence at the manifold while eliminating the annoying whistle found in other helix only throttle spacers. Serrated