Renault EF-Type engine

The EF-Type was a 90° V6 Turbocharged engine developed by Renault Sport, the engine was used by Equipe Renault Elf in Formula One from 1977 to 1985. This engine derived from the CH series designed by François Castaing, the F1 engine was developed by Bernard Dudot.

Renault's decision to use its 1500 cc V6 turbo engines in F1 was one of the boldest decisions ever taken in the sport. In nine full seasons competing against normally aspirated 3000 cc engines, they gave an excellent account of themselves, with:

• One World Championship Runner-Up title in 1983.
• 20 race wins (15 with Renault, 5 with Lotus).
• 50 pole positions (32 with Renault, 18 with Lotus).
• 51 podium finishes (25 with Renault, 20 with Lotus, six with Ligier).

Ultimately, as a result of their success, all F1 teams adopted turbo engines in the 1985 season.

Engines

EF1

1977-1979

Based on the 2-litre "type CHS" engine and developing 500 hp at 11,000 rpm, this engine underwent several major changes metallurgy, mixed air-water exchanger) before bringing the Renault RS 01 its first points in 1978 and its first pole position in 1979.

• EF1: 1,492 cc Bore 86.0 mm (3.4 in) Stroke 42.8 mm (1.7 in) 7.0:1 Compression, one Garrett turbocharger.

1979-1983

With its two small turbochargers, this engine reduced turbo lag considerably. It brought Renault its first F1 race win with a turbo engine (Dijon, 1979). It would undergo a number of significant changes over the years (electronic injection and two-flap air intake in 1982, water injection at air intake in 1983) and its horsepower would gradually increase, eventually reaching 700 hp. In all, it claimed 15 race wins, 30 pole positions and 19 pole positions. It was also supplied to the Lotus team in 1983.

• EF1: 1,492 cc Bore 86.0 mm (3.4 in) Stroke 42.8 mm (1.7 in) 7.0:1 Compression, two KKK turbochargers.

EF4

1984

This engine marked the return of Garrett turbochargers. Fitted to the Renault RE 50, Lotus 95T and Ligier JS 23, it could not break the dominance of the TAG Porsche engine. It nevertheless notched up 11 podium finishes and three pole positions.

• EF4: 1,492 cc Bore 86.0 mm (3.4 in) Stroke 42.8 mm (1.7 in) 7.0:1 Compression, two Garrett turbochargers.

It was the last engine to be badged "Renault Gordini", as there was now a new name to promote: Renault Sport.

"Type-Bis" early 1985

This engine's defining characteristics were its centralized electronic injection and ignition control systems. Generating just over 800 hp, it powered the Renault RE60, Lotus 97T, Ligier JS 25 and Tyrrell 014. It was responsible for one race win, two pole positions and two podium finishes.

• EF4: 1,492 cc Bore 86.0 mm (3.4 in) Stroke 42.8 mm (1.7 in) 7.0:1 Compression, two Garrett turbochargers.

EF15

mid-1985

With greater fuel economy thanks to its new dimensions and a lower boost pressure, its horsepower nevertheless oscillated between 800 and 1000 hp, thanks to metallurgical developments in the turbochargers. It earned two race wins and five pole positions for Lotus, as well as ten podium finishes (four for the Lotus 97T, four for the Ligier JS 25 and two for the Renault RE 60).

• EF15: 1,494 cc Bore 80.1 mm (3.2 in) Stroke 49.4 mm (1.9 in) 7.5:1 Compression, two Garrett turbochargers.

"Type-B" early 1986

This engine boasted two innovative features that would soon gain widespread acceptance – static ignition and pneumatic valve timing – which allowed it to reach 12,500 rpm. Capable of generating 850-900 hp, it would record two race wins and five pole positions with Lotus, as well as five podium finishes (three with Lotus and two with Ligier).

• EF15B: 1,494 cc Bore 80.1 mm (3.2 in) Stroke 49.4 mm (1.9 in) 7.5:1 Compression, two Garrett turbochargers.

"Type-C" mid 1986

Equipped with a number of new features (cylinder heads, cylinder block, waste-gate, mapping, etc.) and developing more than 1200 hp at 12,500 rpm in qualifying, this engine enabled Ayrton Senna Lotus 98T to notch up four pole positions and three podium finishes to close the V6 turbo era in style.