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Welcome to the website for all information about the Ford Sierra Cosworth RS500 Groep A.

On this site you find a lot of pictures of the original race Cossies and how we have built our own Replica.
Or better how we have evaluate an original race Gr N Ford Sierra Cosworth RS to a RS500.

The Ford Sierra RS Cosworth is a high-performance version of the Ford Sierra that was built by Ford Europe from 1986 to 1992. It was the result of a Ford Motorsport project with the purpose of producing an outright winner for Group A racing in Europe.

Mike Moreton was head of the team that planned to develop an evolution edition aimed at making the car unbeatable on the race tracks. In March 1987, Aston Martin Tickford was signed for the job of converting the 500 cars.

The Cosworth RS500 was announced in July 1987, and was homologated in August 1987.
The main difference to the Sierra three-door Cosworth was the uprated Cosworth'scompetition engine.

Its new features were:

- The Inline-four engine had a thicker walled cylinder block to cope with the rigours of the track.

- Bore X Stroke of 90.8 mm (3.57 in) X 77 mm (3.03 in)

- Displacement of 1,994 cc (2.0 L; 121.7 cu in)

- A larger Garrett AiResearch T04 turbocharger

- A larger air-air intercooler

- A second set of four Weber IW025 "yellow" fuel injectors and a second fuel rail (not activated in the roadgoing version)

- An uprated fuel pump

- An reworked induction system to allow higher power outputs to be realised

- An uprated oil and cooling system

- The rear semi-trailing arm beam had extended but unused mounting points

- Engine output increased to 227 PS (224 hp; 167 kW) @ 6000 rpm

- Max. torque of 277 N·m (204 lb·ft) @ 4500 rpm.


The RS500 also had minor external cosmetic differences to its parent the Sierra three-door Cosworth:
The rear tail gate had a lower spoiler in addition to the upper "whale tail", which had an added lip
Discreet RS500 badges on the rear tail gate and front wings
A redesigned front bumper and spoiler to aid cooling and air flow, including the removal of the fog lamps and their replacement with intake grilles to supplement brake cooling.

Touring car racing

 In August 1987, the Sierra RS500 Cosworth was homologated with a larger turbo, new rear deck spoiler and an extra 100 horsepower. Fords took pole position in all the remaining six 1987 World Touring Car Championship events, and was first over the finish line in four of them. Disqualification of the works Eggenberger Motorsport cars from the 1987 Bathurst 1000 in Australia for wheel arch panel irregularities deprived Klaus Ludwig and Klaus Niedzwiedz of the world championship. The Eggenberger Motorsport team did however claim the entrants' prize.[4][5] Eggenberger won the 1989 Spa 24 Hours. Robb Gravett won the 1990 British Touring Car Championship in a RS500.


 The RS500 was successful in Australian touring car racing with Dick Johnson Racing dominating the 1988 and 1989 Australian Touring Car Championships, with Dick Johnson and John Bowe finishing one-two in both years. Early in 1988, the Johnson team also took the step of homologating a modified Ford nine-inch axle for the Sierra, eliminating the car's drivetrain weakness and allowing the cars to be driven harder with less fear of failure. This was also seen as essential in Australia which used standing starts compared to the rolling starts used in Europe


 The RS500 won the Bathurst 1000 twice; in 1988 with Tony Longhurst and Tomas Mezera and in 1989 with Johnson and Bowe. It also won the 1988 Sandown 500 with Allan Moffat and Gregg Hansford. Robbie Francevic won the New Zealand Touring Car Championshipin 1989 and 1990 for Mark Petch Motorsport.

Major series and race wins by the Ford Sierra RS500 include:

Series wins

Copyright Jan van Elderen