# Manifold Air Pressure (M.A.P)

## What Is M.A.P ?

Manifold Air Pressure is the air pressure in the inlet manifold of a piston engine.

It can be used as an indicator of engine power output.

This is an M.A.P gauge from a Schweizer 269C1.

Manifold air pressure gauges are normally calibrated in 'inches of mercury' (in. hg) which is one way of describing a pressure.

Atmospheric pressure is appproximately 29.92 in. hg at Sea Level, reducing at a rate of 1 inch per 1000 ft of ascent..

### Web References

AvWeb Article on MAP

Rod Machado Article on MAP