The 1987 Sierra Cosworth RS500 set to smash auction records

Regular readers of the Cars and motoring section will have likely noted a story or two about Fast Fords in recent months. 

And there’s a good reason why they’re newsworthy – values have shot through the roof in the last few years, especially 1980s Sierra Cosworths, with good examples easily making six-figure auction sale prices.

But one due to go to the block later this month is set to obliterate all price records that have come before it.

The 1987 example of the limited-edition Sierra Cosworth RS500 is in immaculate condition, having covered only 5,192 miles in its 36-year life. Silverstone Auctions predicts the eighties icon will sell for £150,000 to £180,000 at the end of February when the hammer drops, which will be a world record sum for the in-demand machines.

Given that the 500 road-going examples of the Cosworth RS500 cost £19,950, the pre-auction estimate is nine times that number.

Even when taking historical inflation into account, that 1987 list price translated to £62,360 in today’s money, as our historic inflation calculator shows.

Should the stunning low-mileage Cossie up for grabs in a few weeks meet its higher estimate, that’s still almost three times its inflation-adjusted original price and a near 190 per cent value increase in three and a half decades.  

The Ford Sierra RS500 Cosworth would have cost £19,950 new in 1987. Later this month, Silverstone Auctions expects it to sell for NINE TIMES that figure

Even when taking historical inflation into account, that 1987 list price translated to £62,360 in today’s money

Silverstone Auctions believes this car ‘could well break the previous record’ for a Sierra Cosworth RS500, which currently stands at £132,750

It will be available at the upcoming Race Retro Show on Saturday 25 February at Stoneleigh Park, Warwickshire.

The original Ford Sierra RS Cosworth was the first Ford to wear the Cosworth badge and was presented to the public at the Geneva Motor Show in March 1985. 

It was introduced as a means of homologating the Sierra for ‘Group A’ Touring Car racing, with a requirement that 5,000 cars were built and sold. 

Launched for sale in July 1986 and based on the three-door Sierra body-shell, it was designed by Ford’s Special Vehicle Engineering (SVE) and was powered by a Cosworth-designed 2.0-litre turbo engine of now-legendary repute. At the time, the Sierra Cosworth was a new kind of performance car – a ‘blue-collar hero’ able to humble true sports cars.

The RS500 was announced in July 1987 and had a mechanically uprated Cosworth engine (more like the one to be used in competition), with power boosted to 224bhp, modified bodywork and the cachet of being hand-assembled 

That makes the RS500 the ultimate 1980s Fast Ford.

Launched for sale in July 1986 and based on the three-door Sierra body-shell, it was designed by Ford’s Special Vehicle Engineering (SVE) and was powered by a Cosworth-designed 2.0-litre turbo engine of now-legendary repute

The car will be sold at the upcoming Race Retro Show on Saturday 25 February at Stoneleigh Park, Warwickshire

As shown on the odometer here, the Sierra Cossie RS500 has covered just 5,192. That works out at an average of 144 miles each year since new in 1987

In total 5,545 cars were produced – of which 500 were sent to Aston Martin Tickford for conversion to the Sierra ‘RS500 Cosworth’. 

If the RS Cosworth was a homologation car, the RS500 was an evolution special. 

Once Ford had built the requisite 5,000 RS Cosworths, ‘Group A’ rules allowed an upgraded ‘evolution’ model to be launched. This could carry changes focused on improving its racing potential, provided Ford sold 10 per cent of the original number as road cars, hence the 500.

Around fourteen years ago, the vendor – described as ‘a knowledgeable and particularly fastidious enthusiast’ – decided to add this RS500 to his collection and embarked on finding the best example there is. 

He knew what he wanted but took the precaution of enlisting the help of a friend who was a marque expert. 

They considered a number of cars, including some lovely examples, but were focused on finding the best RS500 they possibly could. 

A number of other contenders were rejected before stumbling across ‘E378 TKN’ – arguably the best condition Cossie in the country. 

The vendor bought the car in 2009 having earmarked the super-collectible Ford Sierra RS500 Cosworth for his collection and undertook a painstaking search for the best example in the country

The total original car comes with matching engine and chassis numbers and is believed to be one of the best-kept Sierra RS500 Cossies in the country

The Ford Sierra RS500 Cosworth is famed for its enormous ‘whale tail’ spoiler. Values of these cars has skyrocketed in recent years, with a number of examples selling for winning bids at auction well exceeding £100,000

Its originality was unmatched, the mileage nominal – averaging 144 miles each year from new – and the car had patently been cared for.

It is one of the 392 black RS500s produced. 

Ford had intended to make all the RS500 examples in black but the Genk factory in Belgium where the Sierra was assembled didn’t have enough examples in this colour to send to Tickford. 

The rarest colour option is Moonstone blue, of which there were 52 vehicles. The remaining 56 models were the full Essex-spec Diamond White.

Although very lightly used during the vendor’s tenure, it was regularly serviced and maintained during this period by Tremona Garage of Southampton, a local specialist widely recognised as being hugely knowledgeable when it comes to Fords from the seventies, eighties and nineties.  

‘The attention to the detail of this car’s maintenance cannot be understated,’ Silverstone Auctions.

It’s even being sold supplied with a selection of spare – extremely rare – original oil filters, fuel filters and other parts. 

The auction lot even comes with a selection of totally original spare parts, which are like gold dust today, such is their rarity

On buying this car, the vendor also purchase of a set of period RS500 wheels and tyres. This was so that they could remove the date-stamped originals to carefully store them rather than have the factory wheels and tyres bear the weight of the car for prolonged periods

The car barely looks used with the seats showing zero signs of use. Even the carpets have been meticulously preserved and covered at all times

‘This ‘forensic’ attention to originality is further illustrated by our vendor’s purchase of a set of period RS500 wheels and tyres in order that TKN’s date-stamped originals can be carefully stored and not have to bear the weight of the car for prolonged periods,’ the auction house says. 

‘This diligent approach explains why this gleaming black RS500 may well be the best you have ever seen.’

Silverstone Auctions added that it is its ‘hope and belief that it could well break the previous record’ for a Sierra Cosworth RS500.

The current world record amount paid for an eighties Fast Ford Sierra at auction was achieved at another Silverstone sale last year, with a non-RS500 Cosworth with 9,000 miles of the clock changing hands for £132,750.

The highest known price paid for one of the 500 examples of the RS500 built is £122,400 back in 2017.  

Ford Sierra Cosworth RS500: A brief history

The Ford Sierra Cosworth RS500 for created so that highly-strung versions could be used for racing in series like the British Touring Car Championship

The Ford Sierra Cosworth RS500 uses a specially-built 2.0-litre turbocharged Cosworth engine producing 224bhp – which could be upped to 400bhp when modified for competition.

The car maker needed to produce at least 500 examples for road and race use in order to qualify to run in Touring Car series’ and other championships that used road-going models.

These cars featured numerous aerodynamic enhancements that have since become a thing of legend among collectors.

That includes the 30mm lip spoiler applied to the tailgate to increase downforce, sweeping front splitter, and larger cooling ducts for both the brakes and the engine intercooler. 

The cars were exclusively available through 90 nominated RS specialist dealers and went on sale in Britain on August 1st, 1987 at a price of £19,950.

The Cosworth RS500 went on to become a popular model among race teams, dominating the paddocks of touring car championships