- Dutch sportscar maker Donkervoort has paid tribute to its founder’s 70th birthday with the world’s first 2G production car.
- The Donkervoort D8 GTO-JD70 has been tested beyond 2G of lateral acceleration (cornering performance) on its standard road tyres.
- Only 70 JD70s will be built – one for each year of founder Joop Donkervoort’s life, so far – and more than half have already been sold.
- Donkervoort has matched the JD70’s astounding cornering potential with straight-lineperformance by using to a 415bhp version of Audi Sport’s 2.5-litre, five-cylinder turbo motor.
- The JD70 weighs less than 700kg, with some specifications pulling the mass down to 680kg in road trim.
- The JD70 flies from zero to 100km/h in 2.7 seconds, with 1.02G of longitudinal acceleration.
- It accelerates from 0-200km/h in a certified 7.7 seconds on its way to a 280km/h maximum speed.
- Side exhaust pipes have returned to Donkervoort, complete with a particulate filter.
- Groundbreaking EX-CORE® not only keeps the JD70 astonishingly light, but immensely strong and is the only carbon-fibre technology capable of delivering extremely complex pieces.
- The first Donkervoort in history with optional, lightweight power steering.
The D8 GTO-JD70
The Donkervoort Automobielen D8 GTO-JD70 has been developed as a tribute for the 70th birthday of its founder, Joop Donkervoort.
Powered by an optimized, endurance-racing version of the crushingly strong Audi Sport 2,5L five-cylinder turbocharged motor, the JD70 weighs less than 700kg. It is not a specialist track car, and has been developed with both the road and the racetrack in mind.
The next installment of the supercar-killing Donkervoort D8 GTO legend will smash through the 2G barrier to deliver the astounding cornering ability to match its crushing acceleration. The D8 GTO-JD70 will be capable of pulling more than 2G of lateral acceleration in corners, even in its standard trim and on its standard Nankang tyres, and more than 1G of acceleration. It has also moved into a bold new world with the availability of fully adjustable, electric power steering to reduce the physical driving effort while maintaining Donkervoort’s traditional steering intimacy.
“The JD70 has moved beyond the normal measures for acceleration and braking and we’re using G forces now, but the car is still a pure driver’s machine like nothing else on the market,” Donkervoort Automobielen managing director Denis Donkervoort said.
“The JD70 is the distillation of everything we know and everything we’ve learned on the road and the racetrack, from track days and from customer talks and, of course, from Joop’s own ideas on what a supercar should be to its driver.
“Donkervoort has worked to deliver a supercar for people who ache for the heightened senses and the purity of unfiltered driving experiences, and the JD70 has been designed to allow drivers to form an unshakeable bond with their machines,” he said.
Only 70 JD70s will be built – one for each year of Joop’s life (so far) – with the first deliveries scheduled for June 11, 2020.
The D8 GTO-JD70 will start from €163.636,36 (before taxes).
POWER WITH CONTROL
The most powerful Donkervoort ever made, the 2.5-litre, in-line five-cylinder motor has been developed by Audi Sport to generate 415bhp (310kW) of power and 520Nm of torque. The engine delivers its peak torque from only 1750rpm and holds it until 6350rpm – a point in the rev range where most cars are developing their peak power. It continues climbing to deliver its power peak from 5850rpm until 7000rpm, meaning there is a seamless transition from the torque to the power peaks, giving the JD70 tremendous strength at all points in the rev range.
The 2480cc engine has won its class (2.0- to 2.5-litre) in the International Engine of the Year awards 10 years in a row, and the JD70 boasts 15bhp more than the engine delivers for the current Audi RS 3 and the TT RS. Its unique rhythm is delivered by alternately firing neighbouring cylinders and the more distant cylinders. The engine is as sophisticated as it is strong, with continuous adjustments to the intake and exhaust camshafts delivering variable valve timing. It is even surprisingly green for a super sportscar, with just 191 grams/km of CO2 emissions on the WLTP cycle.
Its layout matches that of the previous D8 GTO-40, providing enough engineering familiarity to comfort loyal Donkervoort fans and enough raw performance and character to draw in new customers.
The JD70’s exhaust system is completely new, allowing the car to pass the EU6D-Temp emissions tests. Incorporating a new catalyst system, the exhaust exits the side of the car, ahead of the rear wheels, which reduces weight thanks to shorter pipe lengths, and it has also been tuned to deliver an even more emotional engine sound into the car. It contains a standard particulate filter, which presented its own challenges for Donkervoort.
“We found a way to turn that complication into a positive,” Donkervoort’s Managing Director Denis Donkervoort said.
“The filter took away just enough of the exhaust noise that we could bring back the side-pipe layout that our customers love, and still pass all the noise regulations comfortably.”
The engine’s undoubted strength will be matched to a close-ratio, five-speed manual gearbox. While other carmakers have more gear ratios, the length of the in-line five-cylinder engine dictates a five-speed gearbox. The boosted torque from the engine delivers so much torque at very low speeds that we can take advantage of the lighter weight and complexity of the five-speed gearbox and drivers don’t need to make as many gear changes.
The core of the transmission has been sourced from Tremec, though a mountain of internal work has been done to make it more suitable for sportscar work, including a short-throw gear lever, reinforced synchromesh and gear lockings. It has been totally re-engineered internally by specialist in The Netherlands, while the Ford-sourced differential has been stripped out and replaced with a Dutch crown wheel and pinion and all-new English limited-slip hardware.
The biggest change to the driveline has been to retain the close-ratio setup of the gearbox, but to lengthen the final-drive ratio from 3.63:1 to 3.31:1, to take advantage of the engine’s stronger low-end performance and to provide longer highway legs. The change to the taller final-drive ratio does not change the straight-line acceleration.
The new final-drive ratio does help to improve the fuel economy. Even with all of this speed, the JD70’s official CO2 emissions figure per kilometre will be just 191 grams.
That won’t be the end of the powertrain story, though, because a strong relationship with Bosch has delivered rev-matching software for downshifts and even added a full-throttle upshift mode for more spirited driving.
CHASSIS, SUSPENSION AND BRAKING
At the core of the JD70 is a hybrid chassis technology that combines a tubular steel ladder frame with carbon-fibre for added strength and aluminium to reduce weight in less critical areas.
For the first time in its history, Donkervoort will offer electric power steering (EPS) on the JD70. Available as an aftermarket option, the ultra lightweight EPS system has even received Joop’s seal of approval, allowing drivers to push the JD70 to its limits without worrying about their own strength or endurance limits. Sourced from the world of racing, the EPS maintains the pure driving experience and intimate connection expected of a Donkervoort, while adding the ability to adjust to each driver’s preferences.
JD70 owners will be able to comfortably switch from one steering setting for track days to another setting to drive in the city. It even gives drivers the chance to change the weight of the steering to suit their moods. The wide-track suspension system will feature a double-wishbone layout at each corner, with trailing arms at the rear end. There are three-way adjustable Intrax dampers at each corner and their internal engineering has been completely redesigned. The coil springs are custom made for Donkervoort and the front and rear anti-roll bars are also adjustable. The JD70 has a variable traction-control system, but its operation and its intervention strength will be at the choice of the driver at all times.
All Donkervoorts are exceptionally light, which can create a goal conflict between generating confidence-building braking power under enthusiastic driving on the road or the track, and maintaining enough heat in the brakes for strong emergency stopping power on the motorway.
Donkervoort has chosen specialist Italian firm Tarox for the braking hardware, which includes 310mm x 24mm wave-pattern discs and six-piston, monobloc calipers at the front. The rear end uses a single-piston caliper setup with 285mm x 24mm discs, though a more powerful six-piston caliper is available as an option. The brake system does not run servo assistance, though a Bosch Race ABS system is an option for track-focused drivers.
One of the major changes has been, after thousands of kilometres of road and track testing, the switch to Nankang as the original equipment tyre supplier. The Nankang AR-1 compound is harder, and delivers longer tyre life than the previous tyre, yet it provides more mid-corner grip and helps the JD70 beyond the 2G barrier. The front tyres are 235/45 17 in size, while the rear end uses 245/40 18 tyres.
The front tyres wrap around 8 x 17” forged alloy wheels, while the rear end uses larger 9 x 18” wheels. Super lightweight carbon-fibre rims are a factory option.
The simple act of moving the exhaust to the side of the JD70 has freed up a lot of space that can be used to enhance the aerodynamic downforce at the rear of the car.
Along with the new, second rear diffuser, which delivers 80kg of rear downforce, the redesigned nose and the new louvres in the cycle wing wheel covers generate an extra 50kg of downforce at the front.
The louvres built in to the trailing edge of the front cycle wings release any air that builds up between the tyre and the wing, which raises the top speed of the car while reducing aerodynamic lift and drag.
“Again, we turned a technical difficulty into our advantage,” Denis Donkervoort explained. “We added the double diffuser in the space where the exhaust system used to be. Not only do we get our side pipes back, but the car became more stable at high speed and in fast cornering.”
Donkervoort’s redesign of the rear underbody section also has the side benefit of delivering more cooling air to the differential.
The bodywork itself is made of a carbon-fibre/Kevlar weave and can be delivered either painted or in a raw, naked carbon look, with a simple lacquer coating in either matte or polished finishes. Even the cycle wings, including their louvres, are carbon-fibre/Kevlar.
The entire front design is now new compared to the GTO-40 and all of the vented pieces are hexagonal in design and they are all made from 3D-printed composites.
WORTH THE WEIGHT
More than 95 percent of the D8 GTO-JD70’s bodywork will be made from carbon-fibre, including a significant amount of Donkervoort Automobielen’s lightweight EX-CORE® carbon-fiber technology, the development of which earned the company European Union innovation grant.
EX-CORE® will not only make the JD70 astonishingly light, but immensely strong and fully compliant with the European Community’s Small Series type approval crash regulations. The technology is used in the single-piece doors, for example, and though it was conceived for automotive use, it has drawn interest from as far afield as cycling, yachting and aviation developers.
There are other significant weight-saving strategies, too, including a lightweight lithium-ion battery that saves 7kg over a standard unit.
The new seats are in lightweight carbon-fibre as well, and the quick-release steering wheel is a multi-function unit, which saves both weight and switchgear in the carbon-fibre dashboard.
PURE DRIVING EXPERIENCE
Suitable for both the road and the track, the JD70 also marks one of the highlights of Donkervoort Automobielen’s 41st year and will continue its philosophical focus on raw driving skill and unfiltered emotions. Unlike modern machinery from traditional or more famous sportscar operations, the Donkervoort JD70 will avoid electronic driver aids wherever possible to maximize the challenge, involvement and purity for its drivers.
Feedback from Donkervoort Automobielen’s loyal customer base confirmed it prefers a car that balances driving comfort with the ability to heighten a driver’s senses with a pure, unfiltered performance-driving experience, allowing drivers to form an unshakeable bond with their machines. A significant number of Donkervoort customer also own collections of classic cars, so the JD70 will allow them to shift manually, drive without power steering, correct their own slides and develop their own driving skills, all in a modern supercar with modern reliability and modern safety.
Like all other Donkervoorts, the JD70 ownership will open a door to a broad range of track days, driver training options, touring and travel events as well as immediate membership of the extended Donkervoort family – both literally and corporately.
Just as no two Donkervoort cars are the same, no two Donkervoort owners are the same. That’s why Donkervoorts can be personalized to extremis, from paint to parts to interiors.
Here are just a few (and by no means comprehensive list of) examples of the breadth of options a JD70 buyer can choose.
- Free-flow, stainless steel exhaust (without a particulate filter).
- Limited-slip differential cooler.
- Bilster Berg roll cage.
- Tighter steering ratio.
- Bosch Race ABS system, M5 Clubsport edition.
- Six-piston Tarox rear brake calipers.
- Luke six-point harness (FIA approved).
- Schroth four-point harness.
- MXS Pista digital colour instrument display, with Wifi data logging and GPS live lap timing.
- Tyre temperature and pressure monitoring.
- Carbon-fibre rims.
- Carbon-fibre transmission tunnel
Customisation and Comfort
- Interior-design package.
- Wind-deflector package, fitted to the window frame to reduce in-cabin turbulence.
- Ultra-light air-conditioning unit.
- A rear-view camera for easier reversing.
- A choice of two different alarm systems.
- Electric adjustable power steering.
- Xenon headlights.