Sierra Sapphire 4x4 
RS Cosworth
1990 - 1992



Some Pictures on these pages are take from the Duke Video range
of videos with their kind permission.

This Sierra Cosworth was based on the 4 door Sierra Sapphire shell.

The vehicle was available from 1990 in both RHD (Right Hand Drive) for the UK market, and LHD (Left Hand Drive) for European market. Approximate number built: 12,250; assembled at Genk, Belgium.

The Engine 
YBG 1993cc block, 16 Valve, turbocharged, 224 bhp engine. 
Bore/stroke: 90.82 mm/76.95 mm. 
Revised head and cylinder block. 
Improved cast iron exhaust manifold. 
4WD Cosworth model's intercooler was enlarged by 25% to further aid charge cooling. 
Catalytic converter. 
Ford EEC IV Management. 
Fuel injection used Weber/Marelli equipment. 
Max torque: 214 lb ft at 3,500 rpm. 
Gearbox and Transmission 
Ferguson patented 4x4 transmission with Ford MT75 gearbox. 
Internal ratios: 1st, 3.62; 2nd, 2.08; 3rd, 1.36; 4th, 1:1; 5th, 0.83 

Final drive: 3.62:1, 22.24 mph per 1,000 rpm in 5th. 

Single dry plate clutch. 

Chassis

Hydraulic power assistance, rack and pinion, lock-to-lock: 2.6 turns. 
Front: Via MacPherson struts, unique RS spring rates, monotube gas damping, thickened (30 mm) anti-roll bar. 
Rear: Separate springs and single tube gas dampers, plus 18 mm rear anti-roll bar, spring rates as per previous 2WD Cosworth. 
Brakes

Front: 278 x 24 mm (10.94 x 0.94 in). 
Rear: 273 x 20 mm (10.74 x 0.79 in). 

System: Four wheel ventilated discs with ABS electronic anti-lock braking and hydraulic assistance. 


Wheel & tyres

Wheels: Unique RS 7 x 15 in alloys. 
Tyres: Bridgestone ER90 205/50 ZR 15 on UK cars. 



Body Work and Interior 
4 Door Saloon 
Cd: 0.322. 1 

Construction: Unitary steel with RS polyurethane panels including front and rear spoilers, side sills and bonnet louvres. Dimensions: Overall length: 4,494 mm (176.9 in); width, 1,698 mm (66.8 in); height, 1,376 mm (54.2 in); wheelbase, 2,608 mm (102.7 in); kerb weight: 1,280 kg (2,816 lb), add 10 kg (22.05 lb) for Cat model. 

Available colours where 

Diamond White 
Flint Grey 
Metallic Magenta 
Optional extras where 

Black leather interior 
Air Conditioning 
On board fuel computer 
Electric tilt and slide sun roof. 
Performance & Economy (Manufacturer's figures)

Max speed: 150 mph. 
Acceleration: 0 60 mph, 6.6 sec. 

Fuel consumption: 22.1 mpg urban; 37.2 mpg at constant 56 mph; 30.4 mpg at 75 mph.