Ford Sierra RS Cosworth 1986 review
Hatchback Petrol
Photo: DieselFordMondeo (CC BY-SA 4.0), via Wikimedia Commons
Overview
The three-door Sierra RS Cosworth is the definitive Fast Ford - a 204 bhp homologation special built so Ford could go touring-car racing. With its whale-tail spoiler and turbocharged Cosworth YB engine, it was the fastest thing with a blue oval for a generation.
Just over five thousand three-doors were built between 1986 and 1987, and survivors with straight bodies and matching numbers are now serious collector cars. Drive one and you will understand why a generation still gets misty-eyed.
UK price from: £42,500
Specifications
| Engine | 2.0-litre turbo inline-4 (1,993 cc) |
| Power | 204 bhp @ 6,000 rpm |
| Torque | 214 lb-ft @ 4,500 rpm |
| 0-60 mph | 6.5 seconds |
| Top speed | 149 mph |
| Fuel economy | ~28 mpg |
| Transmission | 5-speed manual |
| Drive | Rear-wheel drive |
| Production years | 1986-1987 (3-door) |
| Kerb weight | 1,217 kg |
Features
- 2.0-litre turbocharged Cosworth YB - 204 bhp
- Whale-tail rear spoiler for genuine downforce
- Borg-Warner T5 five-speed manual gearbox
- Rear-wheel drive - the last of the sideways Fords
- 0-60 mph in 6.5 seconds, 149 mph flat out
- Built for Group A touring-car homologation
Common parts & prices
| Part | Price (GBP) | Notes |
|---|---|---|
| Front brake pad set | £65 | Performance road pads |
| Clutch kit | £250 | Uprated cover and plate |
| Turbocharger reconditioning | £550 | Specialist T3 turbo rebuild |
| Exhaust system | £450 | Stainless turbo-back system |
| Water pump | £60 | YB cooling service item |
| Head gasket set | £120 | Full top-end gasket set |
Pros
- Iconic status - the definitive 1980s performance Ford
- Thrilling turbo performance and rear-drive balance
- Values have soared - an investment-grade Ford
- Strong specialist support for the YB engine
Cons
- Theft and insurance are serious considerations
- Many have been modified, crashed or cloned - check history
- Turbo and head-gasket issues if neglected
- Running costs are firmly in performance-car territory
Frequently asked questions
How much is a Sierra RS Cosworth worth?
Genuine three-doors in good condition sell for £35,000-£50,000, with low-mileage collectors' cars reaching £60,000-plus.
How do I spot a fake RS Cosworth?
Check the VIN against Ford records, look for correct shell stampings, and verify the YB engine number. Clones are common - buy on history.
What is the difference to the RS500?
The RS500 (1987) was a 500-unit homologation evolution with 224 bhp, a bigger turbo and revised bodywork. It is rarer and worth roughly double.
Is the YB engine reliable?
The YB is strong if maintained - regular oil changes and cambelt services are vital. Neglected cars suffer head-gasket and turbo failures.
Is insurance expensive?
Yes - theft risk makes agreed-value specialist cover essential. Tracker fitment and secure storage are usually required.
