RML’s P39 40SE is street-legal, Le Mans-inspired Porsche 911

• RML Group has revealed the P39 40SE based on the Porsche 911 Turbo S
• Custom car features a wider track and longer wheelbase than the 911 Turbo S
• Peak output is 900 hp versus 640 hp in the 911 Turbo S

British motorsports and engineering company RML Group turned 40 this year and is celebrating with four new projects, one for each decade of its existence.

The first is the P39 40SE, an upgrade package for the 992-generation Porsche 911 Turbo S that was inspired by the LMH race cars that compete at the top level in both the FIA World Endurance Championship and IMSA SportsCar Championship.

According to Michael Mallock, RML’s CEO and son of company founder Ray Mallock, the upgrade will turn the 911 Turbo S into a track monster capable of outgunning the 911 GT3 RS on a racetrack, based on the company’s simulation data.

The company estimates the P39 40SE will lap Germany’s Nürburgring in a time of 6:45, which is 4.3 seconds quicker than the time set by the 911 GT3 RS and more than 30 seconds quicker than the time set by the 911 Turbo S.

The modifications include a boost in power from the twin-turbocharged 3.8-liter flat-6 to 900 hp, versus the stock 640 hp. This was achieved by replacing the ECU, turbochargers, intercoolers, manifolds, and the exhaust system.

The body has also been replaced a lighter and stiffer carbon-fiber design which coverfs a wider track front and rear. According to RML, the wheelbase was also lengthened slightly.

The aerodynamic package has been inspired by a LMH race car and includes a drag reduction system. RML quotes peak downforce of 1,460 pounds at 150 mph, or more than 4.5 times a stock 911 Turbo S.

The price of the P39 40SE upgrade, including the donor 911 Turbo S, is 495,000 British pounds (approximately $538,200). Just 10 examples will be built, with the work taking place at RML’s facility in Wellingborough, U.K.

The other three projects RML will launch as part of its 40th anniversary celebrations include a track car code-named P40, which the company said features Formula 1-inspired aerodynamics, plus a high-performance battery, and an original Aston Martin V8 Vantage with modern mechanicals and a body made from carbon fiber.

The new projects go beyond being a mere celebration; they showcase what’s achievable through the new divisions RML has created to attract customers beyond its usual racing and OEM links. The new divisions add powertrain (including EV technology) and bespoke personalization services, alongside the traditional motorsports and engineering services.