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London is no stranger to supercars – or even ultra-rare hypercars. A simple stroll through the city’s hotspots can sometimes be more thrilling than an entire auto show.
So, when I planned a visit into England’s capital city, I expected nothing less than what Theon Design brought out for the day.
Air-cooled Porsches are experiencing a renaissance. Restomods have become so widespread that it’s easy to feel overwhelmed, yet creating a standout piece requires not just skill but real dedication. Theon Design is rising to the challenge, aiming to build the ultimate air-cooled Porsche 911s.
Based in Oxfordshire, this passionate team specialises in the 964 (1989 to 1994) generation of the Porsche 911. Since 2016, Theon has been creating fully bespoke vehicles, customising every detail to suit the owner’s preferences. This commitment was evident in the two unique creations they brought into London.
I found myself standing across from the Cartier showroom on Old Bond Street when Theon Design co-owner Adam Thawley and his colleague Thomas arrived. The two 964s they were driving – one a Signal Yellow 964 Targa and the other a Midnight Blue Coupé – looked like they’d just rolled off the factory floor.
Parked together, the Theon 964s brought the busy street to a halt. For a city known for its supercars, it was surprising to see so much attention focused on two older Porsches.
We often categorise people as ‘petrolheads’ or ‘non-petrolheads,’ but that feels like an oversimplification. Everyone becomes a car enthusiast when the vehicle is compelling enough. I had a few minutes to soak in the atmosphere and snap some photos before Adam and Thomas prepared to move on to the next stops in their London tour.
Thomas kindly offered me the passenger seat in the Targa, and I seized the opportunity.
Sliding into the car, I was met with an unexpected delight: the interior was both modern and retro at the same time. I quickly appreciated the absence of screens and haptic buttons. Instead, the controls were delightfully old-school – knobs for the heating and pullout switches for the headlights and, most crucially, the exhaust valves. The car’s character transformed when those valves were opened and closed.
We drove through Park Lane and past the Dorchester Hotel, where a crowd was admiring a Koenigsegg Regera. As if on cue, they all turned their heads like meerkats on alert. The sound of two flat-six engines was enough to redirect their attention from the hypercar to Theon’s vintage Porsches.
Our final stop was a quintessential London mews. After we parked, I had the chance to chat with Adam, who founded Theon Design with his wife, Lucinda Argy.
As mentioned, Theon’s rebuilt 911s are based on the 964 generation, but the level of customisation is where they shine. According to Adam, if you gathered five of their commissioned car and their owners in one place, you’d instantly recognise the unique match between each car and its driver.
Common features of Theon Design builds include lightweight carbon fibre panels throughout, except for the doors, which retain a solid, original feel. A carbon tub adds chassis rigidity, which is particularly beneficial for 964 Targas, as they were known to flex more than the 964 Coupé.
These modifications contribute to a significant weight reduction – around 300kg (661lbs) in total. A Coupé weighs around 1,100kg (2,425lbs), while the Targa comes in at about 1,200kg (2,645lbs). Despite the weight loss, it’s not all about compromise; interiors are usually upholstered with roughly 100kg (220lb) of leather!
The engine options range from a 3.6-litre producing 285hp to a 3.8-litre with 370hp and a 4.0-litre that churns out 400hp. Supercharged and turbocharged options are also available. These engines are paired with either a Porsche Getrag G50 5-speed manual or an HSC-200 6-speed gearbox, sending power to the rear wheels. My smooth ride in the Targa was thanks to the TracTive ACE (Active Controlled Electronics) fully adjustable suspension, set up specifically for touring.
The starting prices for Theon’s bespoke 964s are £410,000 (approximately US$516,000) for the Coupé and £430,000 (US$541,000) for the Targa.
The Targa, codenamed GBR-05 as the fifth car delivered to the UK, was commissioned by a returning client who already owns a Coupé. Built to touring specifications, the car prioritises comfort and luggage capacity for long journeys. In contrast, the Coupé, codenamed USA-01 as the first American delivery, is geared more toward sports performance. Its owner, a racing driver, requested a mode switch with options for city driving, track use, and two distinct sports settings. These bespoke builds, with their custom features, come in at around £600,000 (US$755,000) each.
The automotive world has been inundated with restomods, and it’s not hard to see why. Modern cars often fail to captivate enthusiasts, driving them towards older vehicles. Restomods bridge this gap, offering the reliability and comfort of contemporary cars while preserving the timeless charm of classics. While not all restomods are created equal, what Theon Design are building are arguably some of the very best.
I shot a video during my time in London with these two special 964s, and you can check that out by hitting the play button above.
Jathu Thillai
Instagram: jathuthillai
www.jtoncars.uk
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