Theon Design, to those that are deeply intertwined in the world of bespoke Porsche 911 restomods and customs, is a name that is up there alongside the likes of Singer and Straat. Through the application of engineering and aesthetics, they transform what was already a spectacular car into something truly special, often in the arena of it being a one-of-one custom.
In that vein, Theon Design was commissioned by a customer in Belgium to create a one-off bespoke Type 964 Porsche 911 that mixed both the purest essence of the air-cooled generations, with the power and handling of the latest water-cooled generations. To do this, as with all bespoke designs, the donor car, the customer’s original Type 964, was stripped back to bare metal, all parts off, and then build from the ground up again with an exacting level of detail.
This also included stripping the 3.6L air-cooled flat-six to its nuts and bolts, then re-engineering it to be “Better than new.” This included installing independent throttle bodies, flowed and ported heads, a lightened bottom end, motorsports-grade Mahle barrels and pistons, Carillo connecting rods, and custom camshafts.
To this re-engineered power unit, a Rotrex supercharger has been mounted not on the top or back of the engine, but instead to the side, where the original air-conditioning unit for the Type 964 sat. As part of the re-engineering, the mounting points have been significantly reinforced to motorsports-grade, ensuring there is no movement or flex. As well, the Rotrex supercharger itself is custom designed, with significant cooperation with Rotrex in Denmark, so that it uses a centrifugal traction drive to give the highest possible responsiveness and instant power.
To balance out the positioning of the supercharger, twin charge coolers are mounted on the opposite side of the engine, and use a Theon Design trademark water-ethanol exhange system to rapidly cool any air that is passing into the engine. This also negated the need to cut ducting into the Type 964’s body, keeping the classic look and shape intact.
As it was rebuilt, the car was also redesigned with significant lightening measures and materials, often calculated using CAD and CFD to ensure Porsche-level handling and response without compromising structural integrity. With this in mind, Theon Design was able to bring the car’s total wet weight down to 1,265 kg (2,789 lbs) from the original car’s weight of 1,375 kg (3,031 lbs). Pair this with the supercharged engine that creates 400 HP and 367 lbs-ft of torque, and to say that the BEL001 is rapid is understating the fact.
However, the BEL001 has been engineered to handle that power, as it has been fitted with custom switchable adaptive dampers from TracTrive. In a bespoke first, the BEL001 has five suspension modes, from Grand Touring all the way to Race, honed and programmed in by development engineers from Theon Design in conjunction with vehicle dynamics and geometry experts from Centre Gravity.
Much of the body has been redone in Formula One grade carbon fiber, and has been mildly reshaped to call on both the earlier “long hood” style 964’s with the wider hips and back end of a ST/G-series later 964. As well, the car has been rebalanced, removing the old, heavy air conditioning unit, which was mounted high in the engine bay, and replacing it with a lightweight modern a/c unit mounted low and forward, under the hood. As well, the old wiring loom has been completely replaced with a modern, high-tech loom that significantly reduced both the weight and number of wires in the loom itself.
That same level of detail and engineering excellence carries through to the interior, which went through several iterations in collaboration with the customer using fully 3D rendered visualizations before the first stitch had been put into the beautiful leather touring seats. Based on the classic Porsche-Recaro grand touring seats, they are shaped specifically for the customer in Belgium, to support their build and frame perfectly. Full 100% grain, hand-dyed tan leather is meticulously stitched and formed to create a “better than new” interior that is the ultimate in custom sporting luxury. Black accents accentuate these seats, and match with the tan and black interior detailing on the dash and console areas.
The gauge cluster has been designed to reflect on the classic Porsche day-glow green against black from their endurance race cars, which sits behind a custom-made, leather-covered, hand-stitched Nardi wheel from Nardi themselves. The final touches of this exquisite bespoke customization is that the “frunk” is lined in black leather over the carbon fiber shell, and a Type 964 RS replica strut brace has been handmade by Theon Design, wrapped in the same tan leather as the seats, and adds just the right amount of sporting flair to the car.
As one would expect, all of this bespoke work, much of it done by hand, comes with a significant price tag. While the exact price of the BEL001 Type 964 Porsche 911 Supercharged is not revealed, Theon Designs simply states that “commissions start at 380,000. Each car is a totally unique collaboration with the customer and takes 18 months to build. Price excludes donor car and applicable local taxes.”
Full photo gallery here: Theon Design BEL001 Type 964 Porsche 911 Supercharged