Oldsmobile 400 425 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] you can count on Speedmaster

you can count on Speedmaster for coolant temperature sensors

Speedmaster gaskets are designed for today's performance transmissions

They feature a chrome plated dipstick and tube that uses a fully polished billet aluminum handle

Speedmaster aluminum crankshaft pulleys are manufactured from 356 aluminum that is heat-treated to T-6 specs

Oldsmobile 400 425 455 MID-AIR™ MidRise Aluminum Intake Manifold [Polished] you can count on SpeedmasterThe 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.