Pontiac 326 350 389 400 428 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] These pulleys are available in

These pulleys are available in your choice of two finishes

These Speedmaster aluminum crankshaft pulleys help to increase horsepower by reducing accessory drag

Keep your camshaft from wandering with Speedamster camshaft thrust plates

They are built from strong

Speedmaster aluminum adapter spacers allow you to adapt Powerglide to Turbo TH400 automatic transmission tailhousing

Pontiac 326 350 389 400 428 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] These pulleys are available inThe Speedmaster MidRise Air design features the identical plenum and runner design as the normal MidRise. The main difference is that there is an open area under the plenum chamber. This feature is sometimes called an air gap design. The air flowing under the plenum provides a cooler charge for the incoming air with less heat transfer from the engine. This cooler air charge provides additional power and torque.