Pontiac 326 350 389 400 428 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] Speedmaster aluminum adapter spacers allow

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

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

Made for drag racing and off-road applications

It is similar to our LowRise

Speedmaster bracket kit works for late '67-'72 GM A-body cars such as Chevelle

Pontiac 326 350 389 400 428 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] Speedmaster aluminum adapter spacers allowThe 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.