FUEL METERING by ENGINE SPEED and MANIFOLD DENSITY

THE speed-density carburetion system meters fuel in accordance with engine rpm, intake-manifold temperature, intake-manifold pressure, and exhaust back pressure. The advantage of the system is that these variables can be read and the carburetor settings directly derived or checked during flight.

A separate fuel-feed control is provided to govern intake-manifold pressure and temperature - the two main factors affecting detonation.