Keeping the costs under control, providing motor racing at a high technical level combined with the best possible safety – that’s the magic formula used for creating the DTM regulations. For the 2017 season, the technical regulations were significantly revised and now, for 2018, they have once again been refined and adapted in several areas. To make sure that the costs are kept on a reasonable level, DTM keeps on relying on a perfected concept with control components. Nonetheless, the engineers have got enough latitude in the areas aerodynamics and engine for proving that they are better than their competitors.
Already last year, the aerodynamics of the DTM cars was changed to reduce the downforce of the cars. This year, further steps were made on the way to achieve this goal. In the future, only one aero flick per side???will be allowed and this flick will be smaller. Furthermore, the side duct was simplified, the side boards below the doors were removed and the number of further aero components also was reduced. Thanks to these measures, the downforce was reduced y about a third. As a result, the handling of the vehicles represents a bigger challenge for the drivers and overtaking will be more probable, this year.
The DTM vehicles feature a DRS (Drag Reduction System). The rear wing now is inflexible, with the upper two flaps being opened by pressing the respective button. The new system therefore features an even higher efficiency and increases the top speed what will result in a bigger number of overtaking manoeuvres. The rear-wing flaps move back into their closed standard position when the driver decelerates or a certain level of lateral forces is exceeded. So, the driver never gets into a critical position and it is prevented that the reduced downforce results in an unstable car. As result of the aero modifications, the handling of the new DTM vehicles represents a bigger challenge for the drivers.
The DTM vehicles feature a high-performance brake system with alloy brake callipers and ventilated carbon-fibre brake discs at the front and the rear. The brake-power distributor can be infinitely adjusted by the driver. Over the course of the season, three sets of brake discs and nine sets of brake pads each for the front and the rear may be used per car.
All the manufacturers involved in DTM work with an engine control unit supplied by Bosch. They are allowed to write the software for the ECU themselves. Data transfer to the ECU while the car is driving is prohibited.
The suspension was completely revised for the 2017 season and mainly consists of control parts. In 2018, another step in this direction was made. Only linear coil springs are used for the suspension and the so-called third element was made redundant.
From the 2017 season, all the cars on the DTM grid – no matter what brand – have been contesting the races on forged ATS wheels. These wheels are aluminium wheels in the dimensions 12x18 for the front axle and 13x18 for the rear axle. The wheels are made of a high-tensile special alloy and meet the highest demands regarding rigidity and precision. The minimum weight per front wheel amounts to 9.5kg and per rear wheel to 10kg.
To prevent the manufacturers’ strategy manoeuvres, the radio communication was already banned in 2017 and the only communication tools between teams and drivers were the pit boards. But this year, the use of this tool also will be limited: the boards only may be used for informing a driver on pit stops and emergency situations on the track and furthermore, the teams only may use figures, letters and symbols that have been approved by DMSB.
Just one control gearbox-differential unit by ZF has been approved for DTM and consequently is used by all the manufacturers. All the vehicles feature rear-wheel drive, a four-disc CFL clutch and a sequential six-speed gearbox.
The minimum weight of a DTM touring car including driver, racing gear, helmet was reduced from 1,125 to 1031kg for the 2018 season.
The only fuel that is allowed to be used is the one stipulated for the respective event (ARAL Ultimate 102). The tank capacity amounts to 118 litres. Refuelling during a race is prohibited.
The steering wheel may be adapted to a driver’s individual liking.The gears are changed by paddles mounted on the steering wheel. The systems that can be controlled via the wheel have been stipulated, such as the beverage pump, the pit-lane speed limiter, the water-spray system for cooling the brakes, the windscreen wiper, the starter and the DRS activation.
In DTM, solely 90-degree V8 engines with a maximum capacity of four litres and four valves per cylinder are used. The air-inlet system must be equipped with two air restrictors. The diameter of these air restrictors amounts to 29 millimetres each. Due to the additional race weekend in the 2018 season (now 20 instead of 18 races), the engine contingent a manufacturer may hark back to over the course of a season was increased from seven to eight. The horsepower output of the engines amounts to clearly more than 500bhp.
The tyres are exclusively supplied by series partner Hankook, with the slicks for dry condition having been newly designed, for the 2017 season.The front wheels are shod with the latest spec of the Ventus family tyres in the dimensions 300/680-18 and the rear wheels with the same tyres in the dimensions 320/710-18. Compared to its predecessor, the new tyre produces more grip but also has to cope with a bigger performance drop. Eight sets of tyres are available for every driver per weekend for all the sessions (training sessions, practice sessions and races). Tyre warmers for the slicks are prohibited since 2017.
In the cockpit, the DTM driver is surrounded by an innovative combination of control monocoque and control roll cage.In addition, all the DTM cars are equipped with crash structures at the sides as well as the front and the rear that are supposed to absorb as much energy as possible in the case of an impact. Wearing the Head And Neck Support system HANS became obligatory for the drivers as early as in 2002. Furthermore, the DTM vehicles have got a removable hatch in the roof that allows the extrication team to rescue to the driver in the case of an emergency. The safety standards achieved in DTM are unique and unmatched in touring-car racing all over the world.