Welcome to this week’s FC Throwback, where we hit the archives and take a look back at some of our favourite previous feature cars. This week it’s Jason Balmforth’s 515bhp tuned Ford Sierra RS Cosworth feature from 2015…

Ford Sierra RS Cosworth white tuned modified

If Jason Balmforth’s 515bhp tuned Ford Sierra RS Cosworth is anything to go by, love for Ford’s classic three-door Rallye Sport is just as strong today as it ever was…

Ford Sierra RS Cosworth white tuned modified

Lists that do their utmost to provide a compilation of ‘the best cars of the 1980s’ will almost always include a mention of the Audi Quattro, Peugeot’s 205 GTi and the Porsche 911 Turbo, but you can bet your bottom dollar that Ford’s Sierra RS Cosworth will also rank high among the wild and wacky machines found on these fashionable inventories of yesterday’s automotive heroes.

Ford Sierra RS Cosworth white tuned modified

It’s not difficult to see why the classic Cossie’s popularity has stood the test of time – notwithstanding the racing version’s all-conquering performances in domestic and foreign touring car championships, the road-going three-door Rallye Sport captivated the attention of Joe Public with its iconic ‘whale tail’, its aggressive styling and an impressive-for-its-era 204bhp of raw, unadulterated power that still manages to bring a smile to the faces of Ford fans in the present.

Ford Sierra RS Cosworth white tuned modified

Spotting a Sierra Cosworth on the road in period was just as much of an exciting event as it is today, with men, women and children of all ages often seen gawping at the ballistic Blue Oval (usually as it left more mundane machinery in its wake!). As if to prove the point, 42-year-old Londoner, Jason Balmforth, tells us about the moment that he first laid eyes on a Cossie. “It was the mid 1980s. I was a young lad hurriedly making my way to school. I remember stopping dead in my tracks as I spotted the most incredible car spinning slowly on a giant Lazy Susan in the showroom of the Ford dealership that I had to walk past en route to my first lesson of the day. The Blue Oval that I was staring at was none other than a Sierra RS Cosworth. I’ve been in love with the model ever since!” he smiles.

Ford Sierra RS Cosworth white tuned modified

A three-door Cossie remained at the top of Jason’s list of ‘must have’ motors throughout his formative years. Perhaps unsurprisingly, crippling insurance premiums (coupled with an ever-decreasing number of solid examples of his dream drive) prevented him from laying his hands on a Rallye Sport that he could call his own when he first hit the road. Sensibly, he attempted to soften the blow by taking charge of a succession of alternative four-wheelers that had galloped out of ol’ Henry’s stable.

Ford Sierra RS Cosworth white tuned modified

“My first car was a Mk3 Escort estate equipped with an RS Turbo powerplant. I’ve also owned an XR2 with a 1.9-litre CVH beneath its bonnet, a pair of XR2is and a Mk2 Cortina GT. They were all great cars, but obviously no match for a three-door Cossie,” confirms our man from the big smoke.

Ford Sierra RS Cosworth white tuned modified

It wasn’t until the summer of 2008 that the Diamond White wonder that you see on the pages before you rolled into Jason’s life. “I’d spent the previous sixteen years developing my roofing supplies business,” he explains. “A busy work schedule didn’t leave much time for car shopping, but one of my employees stepped forward and told me that a mate of his was selling a white Cossie at a reasonable price. Intrigued, I arranged to view the car. Mechanically, it was a bit of a mess, but I was impressed by the fact that its paintwork was tidy and that its shell was free of corrosion. Needless to say, I ended the day as the proud owner of my very own Sierra Cosworth!” he beams.

Ford Sierra RS Cosworth white tuned modified

The RS that Jason drove home was in a standard state of tune. It was even wearing its original lattice alloys! Even so, the modified nature of his previous cars meant that he was committed to the idea of improving on the factory specification of his new Ford.

Ford Sierra RS Cosworth white tuned modified

“I knew that I wanted to bring the speed and performance of the car in line with modern motors, which is why I contacted a local tuning shop to help with the build of an engine that would be capable of producing over 500bhp,” he continues. Sure enough, his Sierra’s original YB was removed to make way for a fully forged bottom end comprising a 200 long-studded block, Mahle oversized pistons, heavy duty rods, a ported and polished cylinder head, a new turbocharger, high-flow fuel injectors, all new gaskets, a custom wiring loom and a chipped ECU.

Ford Sierra RS Cosworth white tuned modified

Unfortunately, all was not well with the revised nuts and bolts. “I fell out with the engine builder as a consequence of running issues that the car was suffering from after the work had been completed,” sighs Jason. “That’s when I handed the project over to Jano at OddKidd Creations,” he adds.

Ford Sierra RS Cosworth white tuned modified

Jano is well known on the Blue Oval scene, and his Essex workshop has produced some fantastic fettled Fords over the years. He picks up the story regarding Jason’s Sierra: “The car’s fuel rail had snapped, its injectors were loose, fuel pipes were leaking, the installed loom was a mess and the gaskets used in the build of the forged YB were of poor quality!” he cries. Ouch! It might not have been the news that Jason was hoping to hear, but at least his pride and joy was in the hands of someone who was more than capable of righting a few wrongs!

Ford Sierra RS Cosworth white tuned modified

A strip and reassembly of the troubled YB followed, with new 1000cc fuel injectors, fast road camshafts, a WRC head gasket, an uprated valvetrain and a replacement wiring loom thrown into the mix. Twin air injectors, a braced GT3570 turbocharger and a P8 ECU with a custom map worked wonders in releasing stifled ponies, while airflow improvements came in the form of an Auto Specialists inlet manifold, a 2WD Sapphire Cosworth exhaust manifold and a three-inch stainless steel exhaust system.

Ford Sierra RS Cosworth white tuned modified

Meanwhile, the lads at Bara Motorsport rebuilt the car’s rear diff while Jason went on the hunt for a set of wheels and replacement interior. “I bought gold Team Dynamics eighteens that were big enough to house the six-pot AP Racing stoppers that I’d managed to get hold of. I also bagged an ‘as new’ set of Recaro seats that had been taken out of an accident-damaged RS500. The cloth in my Sierra was beginning to show its age, but the new seats provided me with the perfect alternative to the car’s original equipment, ” he says.

Ford Sierra RS Cosworth white tuned modified

The Recaros weren’t the only parts to find their way into the three-door’s cabin. “One of Jano’s customers had removed a Collins Performance engine monitor from the dash of a modified Cossie. I was quick in my efforts to acquire the trick data delivery module, and I’m now able to keep tabs on engine sensor readings without the need to clutter my car’s cockpit with a stack of gauges,” grins Jason.

Ford Sierra RS Cosworth white tuned modified

Those all-important diagnostics are flowing freely following the installation of the OddKidd-tweaked YB. An Airtec alloy radiator, an RS500 intercooler, Samco silicone hoses and an unusual cam cover that has been machined flat (in order to achieve a full text deletion) are also now in place beneath the great white Cosworth’s bonnet.

Ford Sierra RS Cosworth white tuned modified

Elsewhere, Koni adjustable dampers, 30mm lowering springs and a mass of Powerflex polyurethane bushes have vastly improved the car’s handling abilities, not least of all when Jason is pushing his super Sierra into corners at speed. “I’ve waited my whole life for a powerful three-door Cossie. The fact that I’m now in possession of one that is chucking out over 500bhp is something I intend to take full advantage of!” he confirms.

Ford Sierra RS Cosworth white tuned modified

With OddKidd Creations and a host of other tuning firms offering comprehensive YB tuning and maintenance services, it looks as though the Sierra RS Cosworth’s future is set to be every bit as bright as its celebrated three-decade long past. Here’s to the next thirty years of this most excellent of fast Fords!

Ford Sierra RS Cosworth white tuned modified

TECH SPEC FORD SIERRA RS COSWORTH

ENGINE
1993cc YB Cosworth, 200 block, long studded, Mahle oversized forged pistons, forged connecting rods, Mocal remote oil cooler, ported and polished cylinder head, WRC head gasket, uprated valve springs and retainers, BD camshaft profiles, machined cam cover with text deletion, OddKidd Creations custom wiring loom, P8 ECU with custom map, twin air injectors, 1000cc fuel injectors, Bosch 044 fuel pump, Weber fuel pressure regulator, high-flow fuel rail, K&N cone air filter, Auto Specialists inlet manifold, GT3570 turbocharger, CR Engineering actuator, turbo brace, polished turbo heat shield, Bailey dump valve, RS500 intercooler, Airtec alloy radiator, anti-lag, wasted spark conversion, uprated 8mm ignition leads, Samco silicone hoses, 2WD Sapphire Cosworth exhaust manifold, 3-inch stainless steel exhaust system, polished fluid reservoirs.

TRANSMISSION
Borg Warner T5 five-speed manual gearbox, Helix six-paddle clutch, plated differential.

SUSPENSION
Koni adjustable dampers and 30mm lowering springs, polished top mount covers, Powerflex polybushes throughout.

BRAKES
AP Racing six-piston front calipers with 360mm grooved discs, factory rear calipers, performance pads.

WHEELS & TYRES
7x18inch Team Dynamics multi-spokes painted gold, Yokohama Parada Spec 2 215/35R18 tyres.

EXTERIOR
Diamond White paintwork, clear front indicators, replacement rear graphics, RS mud flaps.

INTERIOR
RS500 Recaro seats, Collins Performance engine monitor, Kenwood head unit, RS Owners Club floor mats.

THANKS
Thanks to Jano at OddKidd Creations, and to my wife, Shelley, for her ongoing love and support.

Words Dan Furr Photos Dan Pullen