Pontiac 326 350 389 400 428 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] Made from durable 16-gauge steel

Made from durable 16-gauge steel

it ensures optimal oil flow and reliability under extreme conditions

Get the additional clearance you need for your belt or gear drive timing system with Speedmaster water pump spacers

Convert any one-piece GM TH400 case into a two-piece case with our Speedmaster TH400 case adapter

and stress that the planetary gearset is subject to

Pontiac 326 350 389 400 428 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] Made from durable 16-gauge steelThe 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.