Making around 950bhp, this is the UK’s first right-hand-drive twin-turbo Ford Mustang S550. It also happens to be the owner’s first Ford…

Feature from Fast Ford magazine. Words: Simon Holmes. Photos: Jason Dodd.

While most people’s first experience of a Ford was a low-power Fiesta or Escort, we don’t think anyone can match Reuben Grech’s first Ford – this highly-modified twin-turbo Ford Mustang GT (check out our Mustang GT buyer’s guide).

Not one to do things by halves, Reuben bought the car brand new and certainly didn’t expect to modify it to this level. But once he started, it proved to be a slippery slope.

He says, “When I saw it, I thought I had finally found a car that was good as it was without having to modify it.

Twin-turbo engine in Ford Mustang s550

“But nearly £50,000-worth of modifications later, I can clearly see how wrong I was. I started modifying it four months after I bought it, and it just went downhill from then; it’s has been a work in progress ever since.”

Reuben’s previous cars included Honda, Toyota, Vauxhall, Nissan and Kia hatchbacks, which made the Ford Mustang GT quite a leap. But there was good reason for that.

He says, “As a kid, I was always mesmerised by the Ford Mustang. But since they only came in left-hand drive, I thought it was not reasonable to own one in Malta, where I was born, or in the UK, where I live.”

Side shot of twin-turbo Ford Mustang

Back in 2016 Reuben was looking for a new car and was about to buy the Honda Civic Type R FK2, but at the last minute learnt that the right-hand-drive Mustang had arrived in UK showrooms. Eager for a test drive, he promptly visited the local dealership.

Reuben recounts, “I walked into the showroom and this Mustang was the first car in front of the door. It was love at first sight. After driving the demo car, I was told there was a 12-month wait but then asked about the car in the showroom – which was a cancelled order. I paid the deposit and picked it up three days later. It was the shortest time I ever had to wait for a brand-new car.”

Not one to keep cars standard, a range of modifications followed over the next few years as Reuben made the Mustang his own – from bigger wheels and uprated suspension to interior and exterior improvements.

“I kind of wanted to keep some sort of a sleeper look – so not all out on the outside. But I knew I wanted to go all out on power, noise and handling,” Reuben says.

Front 3/4 of twin-turbo Ford Mustang

As a result, he opted for a subtle approach, although admits he got hooked on carbon fibre, which is how the front splitter, canards, rear spoiler and even propshaft followed. Similarly, the cabin remains relatively standard, as he liked the general look and feel, although couldn’t resist adding green and carbon fibre touches to replace the chrome.

While modifying the car, Reuben also made full use of it on the road, track and shows, which is how he came to create the Mustangs Unleashed UK club.

Driven to continuously improve and develop the car, the most serious modifications followed as Reuben could no longer resist the urge for forced induction. Although supercharging seemed the obvious default option as a proven modification, with readily available kits that are simple to install, Reuben just had to go a different route.

He explains, “There are various reasons why I wanted turbos, but the main one was because I wanted to be different, and I simply wanted the first in the UK.”

But there was far more method to the madness than taste, as the track days had made Reuben wary of adding more heat in the engine bay and the low-mounted turbos would also keep the centre of gravity down. Plus he did not want to add more weight ahead of the front wheels because he already found the GT very front heavy.

He says, “Turbos also gave me the flexibility to change the power level with a push of a button. It was a no-brainer for me.”

But undertaking the ground-breaking conversion would prove no easy task, as no one had tackled the potential clearance issues before, which meant it took a whole lot of time and effort to simply get the parts, let alone making them fit.

Reuben confirms, “I must admit, it was no walk in the park. At the time, there were no right-hand-drive twin-turbo kits readily available, so it’s been quite a long-winded and painful road. I had been looking at kits from America for two years and eventually managed to locate a company that was willing to give it a go for me. After spending a long time on the phone, I eventually decided to take the plunge and part with my money to be the first test dummy.”

Steeda strut brace in twin-turbo Ford Mustang

The only way for the company to ensure there would be no clearance issues with the pre-made kit was to send various right-hand-drive parts to America, including the exhaust manifolds so that they could be test-fitted on a bench before returning the finished kit.

The drawn-out process took six months until eventually, just before Christmas 2020, a load of boxes turned up at Reuben’s door.

He recalls, “I was the happiest person you could imagine. Obviously, at the time I thought it would be a breeze from then on, as I was under the impression that everything would just fit. But the installation took over three months with various trips to fabricators, exhaust manufacturers, parts suppliers and so on. Around 50 per cent of the installation was either modified or custom-made to fit.”

Spoiler on twin-turbo ford mustang

The timeline also included a lot of waiting for parts to be manufactured and delivered during a badly-timed global pandemic, but the results were worth it, as the custom kit helps the car produce around 950bhp at just 10psi of boost.

With further supporting modifications in place, the car is still used on track, at Santa Pod, and for shows.

“I also use it for aimless joy rides when I need to put a grin on my face,” Reuben adds.

It puts smiles on other people’s faces too, as Reuben tells us people seem to love the way it looks and sounds.

“The twin-turbo Ford Mustang turns heads wherever I go, and I constantly get thumbs-up from passers-by and other drivers on the motorway or at shows. From my understanding, it’s quite scary as a passenger too, because they always go either extremely quiet or start screaming as it pushes them into the seat.”

With a first Ford unlike any other, Reuben plans to keep developing the car. In future, a GT500-style carbon-fibre bonnet and front bumper will be added to the twin-turbo Ford Mustang, as well as a new steering wheel and, in the never-ending quest for more power, meth or nitrous injection.

There’s no talk of replacing the twin-turbo Ford Mustang, but who would if this was their first Ford?

Twin-Turbo Ford Mustang S550 GT images

Tech Spec: Twin-turbo Ford Mustang S550


4951cc Coyote V8, Function Factory Performance custom turbo kit, Comp Turbo Technology 62/62 triple ball-bearing ceramic-coated turbos, ceramic-coated manifolds, custom intercooler, ported 2018 inlet manifold, ARP Oil/Ford Performance oil separator, custom Cobra Sport 3in Venom exhaust system, K&N cone filters, Modular Motorsport Racing (MMR) inlet manifold lockouts, billet chain guides, billet secondary tensioner bracket, billet primary chain tensioners and secondary chains, Coyote billet oil pump gear, Coyote crankshaft gear, ARP/MMR balancer bolt, ATI Super Damper serpentine series harmonic balancer, MagnaFlow 200-cell cats, Turbosmart external wastegates, Race Port Gen V blow-off valves and eBoost 2 boost controller, Injector Dynamics ID1050cc injectors, painted engine cover, expansion tank cover, fuse box cover, brake fluid cover and strut covers


950bhp (owner’s estimate)


Original Getrag MT82 six-speed, Lethal Performance LPXHD twin-disc Kevlar clutch, Lethal Performance billet steel flywheel, McLeod Racing slave cylinder, stainless steel braided clutch line and high-load roller pilot bearing, Steeda clutch spring, QA1 carbon-fibre propshaft, Drive Shaft Shop (DSS) half-shafts, Wavetrac ATB LSD, Ford Performance 3.31:1 ring gear, diff cooler


Pedders Extreme coilovers, BMR Suspension lockout kit, vertical link, rear adjustable camber links, rear lower control arms, rear on-car adjustable rod ends, adjustable sway bars, Steeda tower brace, Pedders camber adjustment top plates, Ford Racing toe knuckle bearings


Front: Brembo callipers painted green, 380mm DBA discs and Xtreme Performance pads; rear: Brembo callipers, 330mm DBA discs, braided brake lines, Castrol React SRF brake fluid

Wheels & tyres:

20×10.5in Velgan VMB8 wheels in gunmetal, 5×114.3 with ET25 with 295/30/20 Michelin Pilot Sport 4S tyres


APR Performance carbon-fibre front splitter, canards and rear spoiler, RGBW sequential tribars and demon eyes, LED fog/DRL lights, custom front grilles, custom badges, black-painted grilles, side skirts, front splitter, diffuser, radiator cover extensions, matt black stripes with green pinstripes


LED lighting, painted dash trim, carbon-fibre screen surround and door handle surround, green steering wheel decal, green door and centre console piping, RTR Vehicles gearknob, Shaker Pro Sound System and subwoofer