Renault F7R engine

The F7R engine is used in Renault Clio Williams, Megane Coupe and Renault Sport Spider. The engine was created because displacement limit for FIA World Rally Championship Group A was 2000 cc and more power could be extracted from F7P (1764cc) engine with more capacity.

Differences between F7P (1.8L 16V) and F7R include increased capacity to 1998 cc, bigger valves, more aggressive cam profile, different crank, larger piston bore (82.7mm compared to F7P of 82.0mm), longer stroke (93.0mm compared to 83.50mm) different exhaust manifold, oil cooler, etc. All this results in more low-down torque and more power. Also F7R is coupled to uprated gearbox (JC5) instead of JB3(1.8 16V). Highly tuned F7R engine was used in Renault's rally car Clio Williams Maxi with power output ranging from 250 to 275 bhp (205 kW). This version was coupled with Sadev 6-speed sequential gearbox (stock Williams 5-speed manual).

Specifications

ENGINE
Induction capacity: 1998 cc
Bore x stroke 82.7 x 93 mm
Cylinders: 4
Valves: 16
Injection: multipoint fuel injected
Compression ratio: 10:1
Maximum power: 108 kW ISO 150 bhp (110 kW) DIN (Megane at 6500 rpm, Williams at 6100 rpm)
Maximum torque Williams F7R: 175 Nm ISO 17.5 mkg DIN (at 4500 rpm)
Maximum torque Megane F7R: 185 Nm ISO 18.2 mkg DIN (at 4500 rpm)
Redline: Williams 6500 rpm, Megane 7000 rpm

Modifications

Popular modifications for this engine:

- Wilder Camshafts
- Flowed head
- Forged pistons; often changing the compression ratio to 12:1(for NA applications) or 8:1(for turbo engines, some machine off material rather than buy new pistons to reduce compression ratio); and forged conrods
- Individual Throttle Bodies (iTB) conversion (reliable 210bhp+ and up to around 270 bhp (200 kW) in race versions)
- Turbo conversion (reliable 210bhp+ and up to 500bhp+ in some applications)
Many people choose turbo conversion over NA power, as power gains are cheaper, but ultimately this leads to a more unreliable engine, with head gaskets failing being the biggest problem!

Other modifications related to the engine include uprated exhaust manifold, modified intake manifold, stiffer engine mounts, uprated gearbox and limited slip differential (LSD), scuttle or foglight intake.