1986 Ford Sierra RS Cosworth


1986 Ford Sierra RS Cosworth

1986 Ford Sierra RS Cosworth

Together, Ford and Cosworth released the Sierra Cosworth RS as a homologation special for Group A rally. Thankfully 5000 examples were needed for homologation into Group A rally and by 1986 the car went into regular production.

The Cosworth-developed YBB engine was a Pinto-based block with a Cosworth aluminum head. It was equipped with an intercooled Garret AirResearch TO3 turbocharger that delivered 9psi of boost, resulting in just over 200 horsepower. While for a road car this power was exceptional, especially given the price, in motor sport it was not ample. Given the fact that the car was also rear-wheel-drive and suffered from turbo lag, it is no surprise it didn’t take any outstanding victories in Group A.

Although unsuccessful in rally, the RS Cosworth was quite capable on the road. It even out-powered and weighed less than the BMW’s E30 M3. As a result the car achieved a top speed of 150 mph with a sub six second run to sixty mph.

Based in the RS Cosworth, 500 special RS500 models were built with a more powerful engine. Eventually the whole project evolved into the Escort Cosworth RS which was a more purpose built machine.

1986 Ford Sierra RS Cosworth

In Detail

submitted byRichard Owen
engineCosworth-developed, Cast Iron, YBB Pinto-Based Inline-4
positionFront Longitudinal
aspirationGarrett AiResearch TO3 Turbocharger
valvetrainBelt Driven DOHC, 4 Valves per Cyl
fuel feedWeber-Marelli Microprocessor-Managed Fuel Injection
displacement1993 cc / 121.6 in³
bore91 mm / 3.58 in
stroke77 mm / 3.03 in
power149.9 kw / 201 bhp @ 6000 rpm
specific output100.85 bhp per litre
bhp/weight161.19 bhp per tonne
torque276.59 nm / 204 ft lbs @ 4500 rpm
driven wheelsRWD w/LSD
front tiresDunlop D40 205/50 VR 15
rear tiresDunlop D40 205/50 VR 15
front brakesVented Discs w/4-Piston Calipers
f brake sizex 283 mm / x 11.14 in
rear brakesSolid Discs
r brake sizex 273 mm / x 10.75 in
front wheelsF 38.1 x 17.8 cm / 15 x 7 in
rear wheelsR 38.1 x 17.8 cm / 15 x 7 in
steeringRack & Pinion w/Power Assist
f suspensionMacPherson Struts w/Lower Control Arms, Coil Springs, Anti-Roll Bar
r suspensionSemi-Trailing Arms w/Coil Springs, Anti-Roll Bar
curb weight1247 kg / 2750 lbs
wheelbase2609 mm / 102.7 in
front track1443 mm / 56.8 in
rear track1461 mm / 57.5 in
length4493 mm / 176.9 in
width1699 mm / 66.9 in
height1377 mm / 54.2 in
transmissionBorg Warner T5 5-Speed Manual
gear ratios:1
top speed~241.4 kph / 150 mph
0 – 60 mph~6.0 seconds
0 – 100 mph~16.0 seconds