The aFe Silver Bullet Throttle Body Spacer for the 5.0L V8 sits between the throttle body and intake manifold to add a set volume of air-mixing space. aFe precision machines all Silver Bullet spacers from 6061-T6 billet aluminum, and its serrated/helix combination design is aimed at optimum airflow into the combustion chamber. If you are searching for a billet TB spacer for a 2015-2016 Mustang GT with a serrated helix design, this is the part.
The case for paying for this spacer rests on aFe's own testing and on the serrated design. The manufacturer reports dyno-proven gains up to +14 HP and +15 lbs. x Ft. TQ (Tested w/ Pro 5R Air Filter P/N: 30-10255), so those numbers reflect a specific filter pairing. aFe also states that the serrated/helix combination reduces the intake whistle found on helix-only spacers. Owners on user forums are more skeptical, and many report little or no gain from spacers in general, so set expectations accordingly.
The manufacturer lists this spacer for Ford Mustang GT 11-23 V8-5.0L, which is broader than the 15-16 in the product name, so verify your model year before ordering. For DIY work, aFe's instructions for other Silver Bullet spacers have you remove the intake tube, unbolt the throttle body, and fit the spacer with its gasket and longer bolts, torqued to 10 Nm. Those sheets cover different part numbers, so confirm the exact steps for 46-33020 with the manufacturer.
The manufacturer states that the serrated/helix combination design reduces intake whistle compared with helix-only designs. Individual results may vary.
The manufacturer lists fitment as Ford Mustang GT V8-5.0L from 2011 through 2023. The product name references 15-16, so confirm your vehicle's application with the manufacturer before purchase.
Owners on user forums report mixed results with throttle body spacers generally, with many reporting little or no measurable gain. The manufacturer's dyno figures are the best available reference for expected output.
This is a bolt-on job that requires removing the engine cover and air intake tube, disconnecting the throttle body harness, and unbolting the throttle body from the intake manifold. Keep the factory hardware in case you return the car to stock. Confirm the spacer's orientation: the engraved side and "AIR IN" marking should face the correct direction, and published instructions for this part conflict, so verify with the manufacturer before tightening. Also reconnect PCV and breather hoses, and reseat all clamps carefully after installation.
