Chevy BBC 454 Oval Port MID-AIR™ MidRise Aluminum Intake Manifold [Black] Speedmaster fuel injectors offer precision

Speedmaster fuel injectors offer precision control of fuel delivery and atomization for increased power

The main difference is that there is an open area under the plenum chamber

Suits: 1-149-004 and 1-149-005 Manifolds

Speedmaster billet aluminum spacers provide the benefits of an open carburetor spacer

Speedmaster brackets are constructed from durable steel

Chevy BBC 454 Oval Port MID-AIR™ MidRise Aluminum Intake Manifold [Black] Speedmaster fuel injectors offer precisionThe 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.