Idle Air Control Valve - IAC These Speedmaster supercharger manifolds are

These Speedmaster supercharger manifolds are aluminum constructed and suitable for competition or street use

and most include bolt-in baffles that can be replaced

They also offer the potential for improved fuel economy by making the engine more efficient

straight ball-milled

Fits big block Chevy rectangular port cylinder heads on standard deck blocks

Idle Air Control Valve - IAC These Speedmaster supercharger manifolds areThe automobile engine is a perfect balance of science and mechanical engineering. Each part is designed to interact with the other in perfect harmony to produce a means of transportation. One very small, but very vital component found in this mass orchestra of mechanics is the idle air control valve, or better known to mechanics as the IAC. Speedmaster offers their version, the IAC valves adjust the airflow to improve motor idling