Ford CVH Lean-burn engine
In 1980 Ford introduced their CVH engine in the Escort 3, as a replacement for the old five-bearing pushrod OHV Kent engine. The engine's designation derives from its design — Compound Valve angle, Hemispherical combustion chamber.
Now the CVH has been re-engineered to make it a true lean-burn engine, capable of running on air-fuel ratios of over 18:1. This meant a change in the cylinder head design to incorporate a lean-burn kidney-shaped combustion chamber to ensure high mixture swirl and therefore more complete fuel burning.