Success with the RS badged Capris and Escorts encouraged Ford to give the Sierra a massive image boost by creating the Sierra Rs Cosworth in 1985. Based around the three door body shell, engineers slotted a turbocharged 2.0 liter twin cam unit under the vented bonnet and up rated the suspension and brakes. The result was an unmissable main street supercar that became the first of a legendary line if Cosworth badged Fords. Originally conceived for Group A saloon car racing championship, just 5000 production examples needed to built by Ford. Ford’s Dunton Special Vehicle Engineering division took the Cosworth from line drawing board to the road in just 14 months, although responsibility for designing a super powerful engine around the standard Sierra engine block was entirely handed over to Cosworth. Like all sporting Fords before it, the RS Cosworth put pace before refinement and was something of a brutal machine to drive and required high levels of skill to extract the best from the car. Like the Sierra XR41 before it, the RS Cosworth attracted a fanatical near cult following. Steel monocoque, three door chassis were installed with the disc/ drum brakes. Five speed manual gearbox was inline, struts front and rear suspension.
The RS only lasted a year in production (although Ford ended up making over 6000 units) before it was followed by a limited run (just 500) of the even more brutal 150 mph RS 500s which had power boosted to 224 bhp. The short run and high morality rate of the RS 550 will make it a sure fire future classic.