Theon Design GBR001 3.8 vs. GBR002 4.0

There has never been a better time to be both filthy rich and looking for an air-cooled 911 restomod. Singer is probably the best weaver of such dreams, its million-plus masterpieces now regarded as true automotive art. But there are numerous other providers, the list including Gunther Works and Workshop 5001 in the US, DP Motorsport and RUF in Germany – the latter now offering the 964-based RCT alongside new products – plus veteran fettlers Tuthill in the UK. To even get on the list to be considered against such opposition, you have to be truly special. Theon Design is.

There’s always the risk of calling something like this too early, especially as the Oxfordshire outfit has only finished nine cars. But the freshly-released pictures of GBR002 that you’re looking at here are so compelling I could hum the rest of the review; the images are always going to be doing the heavy lifting here. It looks gorgeous from every angle, with show-stopping presence from every angle – the subtly enhanced lines of the 964 working so well with the ‘70s details that it could have come from a parallel timeline where the 911 chronology got dealt backwards.

Although we’re predominately using the snaps of GBR002, I actually drove both it and GBR001 (pictured here in London) when I visited Theon last month – these being the first two of Theon’s models to be built for UK customers. The chance to see both up close gave the chance to really geek out with Theon’s founder and creative force, Adam Hawley, who jointly runs the company with his wife Lucinda Argy. Seeing cars in earlier stages of build gives the chance to see just how many changes are made to the base bodyshells, which gain carbon fibre roofs and bonnets as well as heavily flared arches to cover bigger wheels. Theon is also working on what will be its first Targa, with this using a special carbon fibre floor piece to add strength to the structure. Could it work to stiffen up a coupe as well? Hawley smiles: “there’s no reason why not.”

There is a superb example of Theon’s obsessive attention to detail to be found in the engine compartment. It might be hard to look at much else beyond the freshly-finished flat-six motor itself, in GBR001 this is a 3.8-litre engine breathing through individual throttle intake trumpets – with GBR002 having a brawnier 4.0-litre with a plenum kit. On the right-hand side of both is a slightly unexpected shape, sitting next to the oil filler. Closer inspection reveals this to be a cylindrical leather cover that sits over the oil filter. “Yeah, the colour was a little too glaring,” Hawley says, “it stood out too much against everything else. I was already a bit triggered by the yellow of the oil cap.”

As you’d expect for the money – from £380,000 plus the cost of the donor car – every part of a Theon Design 911 can be configured according to the owner’s smallest whim. In GBR001, which I spent most time with, that meant the spectacular Slate Grey paintwork – the same shade as Steve McQueen’s 911 in the movie Le Mans – which looked green in natural light. The interior had been retrimmed with a chequered pattern cloth on door panels and seats. It also had what was clearly a 991-generation steering wheel, which seemed to be looking in the wrong direction historically. GBR002 has a much more traditional deeply-dished three-spoke. The customer is always right.

As with the exterior design, the basic architecture of the 964 hasn’t been hidden, just transformed. Most of the ergonomic foibles remain as well, although a new pedal box means that the driving position is now less offset than it would have been in an original car. The gearshifter sits taller as well, this now working a new six-speed Hewland gearbox (earlier Theons used the standard 964 ‘box.) Yes, there is a carefully designed smartphone holding ledge on the centre console, but there are no glaringly anachronistic details; I loved the way the instruments have been recoloured to match the paint without losing their original design or fonts. The asking price really doesn’t seem excessive when viewing the standard of fit and finish up close.

The top-endy nature of car journalism means the previous 964 I drove was an immaculate Carrera RS from Porsche’s own collection. That was on warm, grippy German tarmac, while I’m driving GBR001 on cold and often greasy British roads. But Theon’s car doesn’t lack anything in pace and even grip compared to my memories of the RS. 

Theon’s engines are all handbuilt to reflect the priorities of the customers ordering the cars. GBR001’s 3.8-litre has an ultra-light flywheel and a lightened bottom end to give it savagely quick responses to the smallest changes in throttle pressure. It is driveable at low revs, but not especially torquey, with the action starting as it gets to 4,000rpm – pulling from there with increasing sound and fury all the way to the 7,500rpm limiter, this set 150rpm beyond the point at which the peak 395hp is delivered. 

Which is why it feels modern 911-fast. Working against a claimed 1,164kg of mass, GBR001 has a power-to-weight ratio that is only slightly down on that of a 992-generation 911 GT3. The new gearchange operates with a beautiful precision and a quick-shift mechanism that makes for minimal interruption on upshifts; the speed at which the engine reacts when unloaded makes rev-matching a satisfying challenge when changing down. It sounds amazing throughout, but especially in the zingy upper reaches. There is a switchable exhaust valve, basically offering the choice between loud and very loud. 

Despite the abundance of urge, it doesn’t feel wayward. Serious work has gone on beneath the surface to tame the 964’s more extrovert handling traits without turning it dull. Mass has been deliberately shifted forwards, with the 12 Volt electro-hydraulic power steering pump and electric air con compressor now located under the front luggage compartment. Together with other changes, including the reduced weight of various carbon panels, that gives a static weight distribution of 45:55 front-to-rear, versus the 40:60 of the standard car. Polybushed suspension and new geometry has stiffened everything up, along with switchable dampers from motorsport specialist TracTive. Bigger wheels mounting modern Michelin Pilot Sport 4S rubber bring serious adhesion. 

But the mission has been to upgrade the dynamics rather than lose the car’s fundamental character. The chunky new tyres – 235/40R18s up front and 275/35R18s rear – have been chosen to keep the same width relationship as the 16s on an original Carrera. The new steering rack is much more direct and quicker reacting around the straight-ahead than a standard 964. There is still the unmistakeable sense of the rear-hung mass of the engine, but it is no longer dominating the driving experience. 

So it is easy to tweak and trim the cornering line using the accelerator – the LSD making it easy to get hard on the throttle early in a turn – but the scarier habits have been eliminated. Even lifting off aggressively mid-corner with the chassis loaded up, a definite no-no in any standard air-cooled 911, didn’t turn it snappy. It feels tamer, but definitely not tame.

It’s already been a great day by the time Hawley and I return to Theon Design’s modest HQ in GBR001. To be immediately offered the chance for a context-adding spin in GBR002, Hawley very keen to show how different it is. The car is still being fettled ahead of delivery to its lucky buyer, and is wearing front-to-rear plastic sheeting to protect its immaculate Oak Green paintwork, which must make it for an odd sight as we take to the local roads. Even a shorter drive is enough to prove this is another highlight.

The 4.0-litre engine’s specs might not seem very different to those of the 3.8. The bigger motor’s peaks of 406hp and 326lb ft are 9hp and 36lb ft higher, and both come fractionally lower down the rev range. But that definitely hasn’t turned it into a torque-heavy lugger – it actually feels much keener at the top end than the already potent 3.8, turning truly savage in the last 1,000rpm before it reaches the redline, with a rasping, hard-edged exhaust note that sounds more race than road. I honestly can’t imagine anyone swapping to a car like this from even the most potent modern 911 feeling like they are missing anything in terms of performance or experience. (And don’t forget, there’s also a supercharger conversion.)

Theon has already become a viral hit, each car it delivers bringing in multiple enquiries from the new owner’s jealous friends and acquaintances looking for something similar. Hawley and Argy admit it is at risk of falling victim to its own success as demand overtakes the ability to supply; the company currently has a year-long waiting list, with cars then taking another 18 months to move through the build process. It’s hard to imagine that situation improving significantly as the word continues to spread. 

So if you’re tempted and able, don’t delay.