Chevy BBC 454 Oval Port MID-AIR™ MidRise Aluminum Intake Manifold [Black] The Speedmaster 9" solid pinion

The Speedmaster 9" solid pinion bearing spacer kit is designed to retain the pinion depth settings for greater strength and reliability

shiny or polished materials

Every Speedmaster flexplate is 29

These manifolds require a universal 4-barrel throttle body

Chevy BBC 454 Oval Port MID-AIR™ MidRise Aluminum Intake Manifold [Black] The Speedmaster 9" solid pinionThe 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.