The letters CHT denote a particular type of 4-cylinder internal combustion engine produced by the Ford Motor Company in Brazil during the 1980s. It is a completely different engine from the CVH engine and should not be mistaken with it. Contrary to the CVH, the CHT was very economical, had a very smooth and low noise profile, inherited from its Renault design.
The CHT (Compound High Turbulence) engine was introduced by Ford in 1984 in the Mark 3 version of the Ford Escort, the first of the series to be released in Brazil.[1] It was later used in the Ford Del Rey, the Ford Verona (a Brazilian Ford Orion), as well as the Volkswagen Gol.
The engine itself is an evolution of the very efficient Renault Ventoux engine, which Ford inherited upon buying the Brazilian Willys/Renault plant in the late 1960s. It has 8 overhead valves OHV, and featured a rotating valve design.
The basis of the engine was to create an internal turbulence inside the piston chambers so that a higher percent of the fuel is burnt. It was very robust and economic with modest performance compared to the competing Volkswagen EA-827, having lower HP, but generally higher average Torque, with the bar much straighter and next to the maximum at any RPM than a similar AP engine. Torque was the CHT engine advantage, being capable to run without much loss of power in very low or high RPM.
It was available too running on Ethanol , which generated at least 10% more power than the petrol model, with about 25% increase on the fuel consumption. It had no problems at all for cold starts and high fuel consumption unlike any other ethanol powered engines.
Three models were originally available:
Later, the engine was tuned for better HP figures and fuel efficience:
In 1987, with the release of the Mark 4 Ford Escort, this engine benefited from some revisions, resulting in the CHT E-Max (maximised economy) version. All the new models featured better torque.
In 1992, a smaller version was released for the Escort and the Gol:
During the Autolatina period (1987–1996) VW used this engine, naming it AE-1600 and AE-1000, but it is basically the same engine. AE = Alta Economia (High Economy).
The CHT 1.6 2nd generation engine received the award of most economical engine of its time, capable of running 17.1 km with one liter of petrol.
In 1996 and 1997 the CHT was gradually replaced by the Volkswagen EA-827 and the new Volkswagen EA-111, in the VW cars, or the newer Zetec-SE 16-valve unit and the older Endura-E engine, in the Ford cars.