The EC and ED family are a series of 3.0-litre and 3.5-litre, naturally-aspirated, V8, Formula One racing engines, designed, developed and produced by Cosworth, in partnership with Ford; and used between and . The customer engines were used by Benetton, Sauber, Forti, Lola, Simtek, Pacific, Minardi, and Tyrrell.
Background
The HB was developed into (100 mm x 55.7 mm) EC V8 for the 1994 season. This engine, producing about 740 bhp @ 14,500rpm, was badged as Ford Zetec-R, and Michael Schumacher won the Drivers' World Championship with Benetton (his first of a record 7 championships), in . This was the last Ford-powered F1 title.
For the 1995 season, the F1 engine regulation changed to 3 litres, and the EC's bore and stroke were changed to 94mm x 53.9mm, resulting in ECA, which was introduced at about , and developed to to at 14,000rpm. It was exclusively used by the Sauber team, whose biggest success of the year was Heinz-Harald Frentzen's third place at Monza.
Customer unit Cosworth ED (not badged as Ford Zetec-R) for non-works teams was also made for 1995 with about 580 bhp for Minardi, Simtek (called the EDB), Pacific Racing (EDC) and Forti (EDD) teams. Minardi realised the power deficiency before the season and asked Magneti Marelli to develop a replacement engine management system, with which the engine was called the EDM. Cosworth later updated the ED to ED 2/4 for Tyrrell and Lola with (94mm x 53.95mm) displacement for 600 bhp, which was used until the end of season.
Cosworth EC (1994) The Cosworth EC is a Cosworth-built and Ford-financed 8-cylinder, 3.5-litre racing engine that was used exclusively by Benetton in the 1994 Formula 1 World Championship under the name Ford Zetec-R. Michael Schumacher won the driver's world championship with the EC this year. The reduced to 3.0-litre version Cosworth ECA, again called Zetec-R, appeared in the 1995 season at Sauber but was far less successful there. It was replaced in 1996 after just two years with the newly designed ten-cylinder engine Cosworth JD in the function of the works engine. As a customer motor, the ECA played practically no role.
In its original form as a 3.5-litre engine, the EC was only in service in 1994. At the same time, Cosworth continued to have the old HB eight-cylinder in its range this year. Because the FIA, under the impression of the fatal accidents of Roland Ratzenberger and Ayrton Senna at the San Marino Grand Prix in 1994 reduced the displacement limit to 3.0 litres for the 1995 season, the EC had to be revised after its first year.
For the third generation of naturally aspirated engines after the DFV/DFZ/DFR and the HB, Cosworth once again opted for the eight-cylinder concept. The main reason was the assumption that by limiting the moving parts compared to ten or twelve cylinders, the overall weight and also the friction losses could be reduced. Like its predecessor, the EC has a cylinder bank angle of 75 degrees. Cosworth changed the bore and stroke ratio in favor of a very large bore. The dimensions given by the factory were 99.75 × 55.9 mm; this results in a displacement of 3494.8 cm³. The EC thus has the largest bore of any engine of the 1994 season; only Renault's RS6 ten-cylinder (98 mm) reached similar values. The large bore also affected the engine's length: at 620 mm (24 in), it was as long as the ten-cylinder Honda, Peugeot, and Renault engines; Ilmor 's V10, which ran as a Mercedes in the Sauber team in 1994, was even 25 mm shorter. Like all other engines of the 1994 generation, the EC had two overhead camshafts for each bank of cylinders, and for each cylinder, there were two intakes and two exhaust valves. The camshafts were driven by chains and gears. The engine electronics came from Ford. With the EC, Cosworth used expensive special materials for the first time: the combustion chambers were coated with ceramic, the connecting rods and valves were made of titanium and the pistons were made of a magnesium-copper-nickel alloy. A piston weighed only 305 grams. Nevertheless, the weight of the EC at 135 kg was roughly at the level of the current ten-cylinder engines. Engine power of the EC was estimated at around 755 hp in race trim and 765 hp in qualifying trim. This meant that the EC was about 30 hp short of the most powerful ten-cylinder engines, but its power to weight ratio, the most important performance figure was on par or even better than the ten-cylinder engines- although these engines were more powerful, they weighed more.
The EC was a very expensive engine to run. A revision was already due after 350 km, so that one engine did not even last a whole weekend.