Do you find all those slick Porsche 911 restomods just a tad boring at this point? Meet the antidote; it’s called the TWR Supercat, a brawny Jaguar XJ-S–based coupe with a 660-horsepower supercharged V-12 and a six-speed manual transmission. It has a suspension and brakes engineered by folks who build race cars, as well as carbon-fiber bodywork designed by a guy who kickstarted his career digitally rendering outlandish machinery for EA’s Ghost Games studio. Subtle it is not. Which is precisely what makes it interesting.
Some Background
Although TWR was established in 2020 by Fergus Walkinshaw and John Kane, those three initials and the Jaguar XJ-S go back a long way. Fergus’ father, Tom Walkinshaw, was a successful Scottish racing driver who founded Tom Walkinshaw Racing—the original TWR—in 1976. That company went on to create and campaign successful race cars for automakers such as Mazda and Rover, and it worked on production cars like the Volvo C70. Early in his storied career, Ian Callum worked for TWR, designing, among other things, the Aston Martin DB7.
But it was with Jaguar that Tom Walkinshaw achieved some of TWR’s greatest on-track successes, most notably winning the 1988 and 1990 24 Hours of Le Mans races with sports prototype cars engineered, constructed, and campaigned in partnership with the storied British automaker. The XJ-S link dates to 1982, when Tom Walkinshaw first ran the big V-12-powered coupe in the European Touring Car Championship. In 1985, TWR’s XJ-S racers finished first and third in the legendary 1000-kilometer race at the famous and challenging Mount Panorama circuit in Bathurst, Australia—Walkinshaw himself putting one of the cars on pole for the race.
“Almost 40 years after my father’s original company dominated the racetrack, we’ve brought the TWR name roaring back with the Supercat,” said Fergus Walkinshaw, acknowledging the special link between the TWR name and Jaguar’s V-12 coupe. The new TWR plans to eventually become an ultra-low-volume manufacturer like Singer. Starting with a 21st-century rework of the XJ-S was an obvious move, Kane says, not just because of the historical links with Walkinshaw but also because, unlike the Porsche 964s many restomodders prefer, donor Jaguars are still cheap and relatively plentiful.
That’s because the XJ-S has long been one of Jaguar’s least loved cars. From the moment it was launched in September 1975, many struggled to see the XJ-S as a legitimate successor to the curvaceous E-Type. “Opinions differ over how good-looking the XJ-S body is,” the editors of Britain’s authoritative weekly, Autocar, diplomatically opined at the time. Their colleagues at CAR Magazine were, characteristically, much blunter and to the point in their assessment, calling the XJ-S’ styling “a dog’s breakfast.”
In recent years, however, there has been a rapprochement of sorts. “A generation that wasn’t born when the XJ-S arrived seems to have discovered it on its own terms,” wrote Richard Porter in his thoughtful reappraisal of the car for the high-end British quarterly magazine The Road Rat. “It’s taken almost 50 years, but now, finally, the XJ-S can be considered not just the last progressive Jaguar. It might also be considered cool.”
So What’s a Supercat?
TWR calls the Supercat a super GT, a car designed to be comfortable enough for a fast cross-continental road trip, yet capable enough for a fun day at the track. Its powertrain is one part of its USP: Other than Aston Martin’s Valour, the Supercat is the only car on the market right now that offers a V-12 engine with a manual transmission. The other part? It’s a fraction of the price of the almost $2 million Aston. The Supercat starts at the equivalent of about $300,000, plus the cost of a donor car, local taxes, and shipping.
You can supply the Jaguar XJ-S, or TWR will source one for you, and it can be either left- or right-hand drive. The XJ-S stayed in production for more than 20 years, but the model TWR uses for the Supercat is the HE produced from 1981 through 1991 and so named because of the “high-efficiency” version of the V-12 engine under the hood that delivered much better fuel economy and more power.
The car is stripped to a bare shell and extensively braced and strengthened by way of a tubular steel structure that includes elements in the roof and pillars, the sills, and across the cowl and rear floor. These elements are connected to new tubular steel subframes front and rear that locate the multilink suspension with redesigned geometry to accommodate the big increase in track width over the standard XJ-S, as well as the engine, transmission, and limited-slip differential.
It’s a similar approach to the one used by race car builders such as AMG when turning a roadgoing GT model into a GT3 race car. The process not only provides a stiff chassis for the suspension to work against, but also allows TWR to cut away most of the stock steel panels and replace them with the carbon-fiber pieces that give the car its dramatic street presence and contribute to a 660-pound weight reduction compared with the standard XJ-S.
Power Play
The V-12 engine is disassembled and the block bored out to increase capacity from 5.3 liters to 5.6 liters. Then it’s rebuilt with remachined cylinder heads, new pistons and conrods, new camshafts, and a new valvetrain that’s an impressive 4.4 pounds lighter than the original. The bespoke induction system features twin air filters near the cowl that feed a carbon-fiber intake manifold leading into a Rotrex centrifugal supercharger mounted in the valley at the front of the engine. The TWR-tweaked V-12, 11 of which were built and tested during the development program, produces 660 hp at 6,600 rpm and 538 lb-ft of torque at 5,400 rpm, Fergus Walkinshaw says.
The six-speed manual transmission is a modified Tremec Magnum. This tough and trusty aftermarket version of the TR-6060 used in the Dodge Challenger Hellcat and Viper, and in the Chevy Camaro, can handle up to 700 lb-ft of torque. The decision to go with a manual transmission was a no-brainer, according to Kane. “It is an enthusiast’s car,” he said. But Walkinshaw says the Supercat can be fitted with an automatic or dual-clutch transmission if customers so desire. “If the demand is there, we can do it.”
The TWR Supercat comes equipped with adjustable traction control that offers four levels of intervention or can be switched off, as well as five different drive modes and launch control. The Dutch-made TracTive dampers also offer five levels of adjustment. Standard brakes are by AP Racing, with vented steel rotors and six-piston calipers up front and four-piston items at the rear. A carbon-ceramic brake package is available as an option. Both setups offer 12-level adjustable antilock brake intervention. All this adjustability is courtesy of control systems and hardware used in race cars.
Rolling Stock
The original Jaguar XJ-S rolled on 15-inch wheels and 215/70 tires. The TWR Supercat squats on forged aluminum-alloy monoblock rims, 18-inchers up front and 19s at the rear, shod with 275/35 and 325/30 tires, respectively. Michelin’s excellent Pilot Sport 4 S is the standard tire, but customers planning to spend time at the track in their Supercat can order stickier Cup 2 rubber.
Oh, That Body
The TWR Supercat’s bodywork is by Khyzyl Saleem, a former graphic designer whose digital renderings of wildly customized cars have attracted a sizable social media following. The Supercat was originally going to be a restomod very much in the Singer style, a carefully cleaned-up and improved version of the original XJ-S. What you see here is a car that echoes Saleem’s digital creations. Los Angeles–based Magnus Walker, best known for his Urban Outlaw Porsches, acted as a design consultant.
“The brief was very open-ended,” Saleem said. “I had quite a lot of freedom to work with the original design and build on it, but everything on the car had to be functional.” The reverse scoop on the hood, for example, is there to provide clearance for the new intake system; the pumped fenders are needed to cover the wider wheels and 4-inch increase in track; the ducktail rear spoiler creates downforce on the rear axle. Speaking of aero, the C-pillars that were the most controversial aspect of the original XJ-S are now genuine flying buttresses, with new venting between the panel and rear quarter being used to direct air over the rear spoiler.
Final Details
Inside the TWR Supercat is a redesigned interior that features a new dash, new center console, new power seats, and new door trims. The instrument panel is a digital riff on the XJ-S original, and the four-spoke steering wheel is like the one used in the 217-mph XK220 supercar that was developed in partnership with Jaguar by Tom Walkinshaw and assembled in his facility in Bloxham, England. The stiffened body structure means the rear bulkhead can be folded down to increase luggage capacity.
TWR plans to build just 88 Supercats over the next three to four years, the number an homage to the Silk Cut Jaguar XJR-9LM’s famous win, orchestrated by Tom Walkinshaw, in the 1988 24 Hours of Le Mans. First customer deliveries are scheduled to occur in 2025.