Can there be too many custom 911 builds aimed at millionaire car lovers? Theon Design thinks not.The British restomod specialist has revealed its latest custom Porsche 911 build, a lightweight carbon-bodied 964 coupe combining the marque’s classic air-cooled character with modern engineering and 421 horsepower.Built as a commission for a private client and tailored to their specific preferences, the latest Theon model draws power from a naturally aspirated 4.0-liter flat-six producing 421 hp and 324 lb-ft of torque. The engine is paired with a six-speed manual transmission and rear-wheel drive, helping deliver a power-to-weight ratio that Theon says exceeds that of Porsche's current 992.2-generation 911 GT3.The vehicle weighs just 2,527 pounds, thanks in part to an extensive carbon-fiber body. Despite the use of modern lightweight materials, Theon continues to retain steel doors on all of its builds, arguing it preserves the familiar feel and tactility of a classic 911.Theon 964 911 restomodThe car is finished in a Crayon Grey paintjob with Lizard Green accents, while sporting smoked lighting elements, custom brushed brightwork, and a Turbonite Porsche crest, while 17-inch wheels and green RS brake calipers sit at the corners.Underneath, the car features TracTive semi-active suspension with five selectable settings, which allows the ride and handling nature to be adjusted from a daily driving style to full-on track use. And a front-axle lift system helps getting in and out of driveways easier.Engine management is handled through a MoTeC ECU and power distribution system. The drive-by-wire throttle has multiple settings from Town and Race modes to a “Raucus” that unlocks full performance, deploys the rear spoiler, and activates a louder exhaust note complete with pops and crackles.The color themes extend inside with dark leather trim surfaces and Lizard Green stitching. Recaro RS seats, bespoke aluminum footboards, and custom-machined vents, door handles and dashboard details reinforce the handcrafted feel. Nods to modern conveniences include wireless phone charging and an upgraded audio system hidden behind a period-correct Becker Mexico head unit.Theon 964 911 restomodFounded by Adam Hawley and based in Oxfordshire, England, Theon Design produces a limited number of air-cooled Porsche 911 commissions each year. The company says every build requires approximately 6,000 hours of development and assembly.Just six new Theon commissions are scheduled for delivery worldwide in 2026, with prices starting at $585,000 before the donor vehicle, shipping, and local taxes.