Marco’s company car: The BMW Driving Experience M4 DTM

Marco Wittmann started the 2016 DTM season in a new livery and with an ambitious attitude. His goal: reclaiming the DTM title. Two years previously, Wittmann had made a successful start to the touring car series season in the Ice Watch design. This time around, he caused a stir in the distinctive blue Red Bull livery. His first win came at the second race weekend in Spielberg. This was followed by further wins in Moscow and at the Nürburgring. The grand finale in Hockenheim was a thrilling affair and the BMW driver kept his cool to repeat his 2014 title win, becoming the youngest two-time DTM champion in history. Marco Wittmann lines up in the legendary BMW M colours in 2018. From bonnet to rear wing, find out all you need to know about Marco’s new company car, the BMW Driving Experience M4 DTM, here.

Development

The first model made its first appearance in the wind tunnel at the BMW Group’s Aero Lab on 22nd April – 13 days before the opening race of the 2013 season in Hockenheim. In the summer of 2013, while continuing with aerodynamic testing, the experts in Munich turned their attention to designing new suspension parts. The new components made their first on-track outing in December 2013 – but still within the BMW M3 DTM at that point. The final parts for the chassis of the BMW M4 DTM were in production by the turn of the year, allowing the BMW teams to assemble the first models of the new car in January and February. Three hundred days after the first test in the wind tunnel, the BMW M4 DTM took to the track for its track debut in Monteblanco on 11th February 2014.

The production version of the BMW M4 Coupé provided BMW Motorsport with a perfect basis for developing the DTM racing car. Hardly surprising, given the fact that the primary goal of the BMW M GmbH engineers working on the BMW M4 Coupé was to create a robust car suitable for use on the racetrack. Among those to make valuable contributions towards achieving this goal were DTM drivers Bruno Spengler and Timo Glock, who took part in tuning tests at the Nürburgring-Nordschleife. “I am proud to have played my part in the fine-tuning,” said Spengler. “The chassis of the BMW M4 Coupé is very sporty. The feedback from the front axle is extremely direct, and the grip on the rear axle is phenomenal. This car is the ideal basis for our car in the DTM.”

Production

The last BMW M car to roll off the assembly line at the main BMW Plant in Munich did so back in 1991. After that, production shifted to BMW Plant Regensburg. Almost 23 years later, the assembly process returned to the main factory – and just a few metres away BMW Motorsport engineers were hard at work tinkering with the racing version of the new car. However, the BMW Plants in Regensburg and Dingolfing were also involved in the development of the BMW M4 DTM. Among other things, the kilometre-long test tracks at the modern production facilities were used for aerodynamic tests. Throughout the development phase, the BMW M4 DTM car was to be seen at what is otherwise the venue for the exhaustive quality control checks performed on all BMW M cars.

Design

Tradition meets the modern day: Light blue, dark blue and red have always been intrinsically associated with BMW on the motorsport scene. As far back as the 1970s, BMW racing cars tasted success on the international stage with the characteristic striped design. Today, the new BMW M8 GTE is just one of the cars that races with the traditional colours in the new design. Bold, modern shapes are derived from the three bars of the BMW M logo with abstracted, high contrast application for maximum visibility at speed. The livery is linked to architectural elements of the car, such as the C pillar’s Hofmeister Knick, lending a visual logic and structure to the impactful, expressive design. The faceted flag motif graphically celebrates the spirit of competition and embodies the essential dynamics of motorsports. A functionally inspired asymmetry extends the iconic theme of driver orientation from BMW interior design to the exterior of the car with an anti-reflective matte black driver’s side hood element. The wedge-shaped lower subdivision sets a forward inclination. Fundamental design elements like these are shared by all the new liveries for the BMW M4 DTM for the 2018 season, and are features of all BMW M Motorsport car designs.

Aerodynamics

The BMW engineers spent the winter break reworking the BMW M4 DTM in line with the specifications for the new technical regulations. The changes could be headlined as “less is more”: downforce has been reduced by one third. As a result, there is now even more focus on the drivers. Some of the modifications are immediately obvious. The side channel of the BMW M4 DTM has been simplified and the side plate below the doors has been removed. In future only one “aero flick” will be used on each side at the front of the car – and that is smaller than its equivalents from last season. The basic geometry of the rear has been retained, but some detail simplifications were made in terms of aerodynamics. The overall result: much less downforce and reduced drag which, depending on the track, will lead to higher top speeds. Under the bonnet of the BMW M4 DTM the third element of the front axle has been dropped for 2018 meaning that there are only four conventional side springs, one per wheel. As a result, the BMW M4 DTM will move more under braking in 2018. In combination with the aero adjustments, this means that there will now be much more focus on the drivers’ vehicle control.

Lightweight construction

The BMW M4 Coupé itself is a prime example of intelligent, lightweight construction. The high-performance sports car weighs just 1,497 kilograms when empty – that is a whole 80 kilograms less than its predecessor. This reduction of weight has a positive effect on the driving dynamics and consumption. This has been made possible by the extensive use of lightweight materials, such as carbon fibre reinforced plastic and aluminium. The use of carbon is also widespread in motor racing. Virtually the entire body of the BMW M4 DTM is made of this ultra-light and durable material. The weight reduction and consequent lowering of the centre of gravity are key to the car’s performance on the racetrack. The weight of the BMW M4 DTM, with driver, is 1,110 kilograms.

Safety

Like the BMW M4 Coupé, the racing version also meets the highest safety standards. Over 50 of the 5,000 plus parts that make up the BMW M4 DTM are standard components, which are used in all DTM cars. One of these is the carbon fibre monocoque, which sets the benchmark in terms of safety in motorsport. With an integrated tank, steel roll cage and additional crash elements, it offers the driver effective protection in case of a crash. Parts like the gearbox, clutch, dampers and rear wing are identical in all DTM cars. This also keeps a lid on development costs.

Engine

The BMW P66 engine in the BMW M4 DTM generates approx. 480 bhp with the air restrictor specified in the technical regulations. It is made up of 800 different components, consisting of 3,900 individual parts. When designing the DTM drivetrain, BMW Motorsport took full advantage of the technological know-how within the BMW Group. The high-tech foundry connected to BMW Plant Landshut accounts for the large cast parts, such as the cylinder head and crankcase – just as it does in the production of the six-cylinder in-line engine for the BMW M4 Coupé. The cast parts are coated and given the necessary heat treatment within the appropriate departments in Munich. The BMW V8 for the DTM is both a sprinter and a marathon runner. It allows the BMW M4 DTM to accelerate from 0 to 100 km/ in about three seconds. Only ten engines are permitted for all eight BMWs over the course of the entire season. Therefore, reliability is a prerequisite to success.

The engine’s power is transferred via a sequential six-speed sport gearbox, which is operated pneumatically using shift paddles mounted on the steering wheel. The gearbox is one of the standard components, which are used by all the DTM manufacturers. It has 11 final drive ratios, which allow the engineers and drivers to react to the respective circuit and engine characteristics when setting the car up.

Steering wheel

Additional status displays and a customised layout of the controls make the steering wheel in the new BMW M4 DTM even more comfortable for the drivers to use. The individual buttons can be allocated as the driver desires. As with the racing car, the gears on the BMW M4 Coupé can also be changed using shift paddles on the steering wheel, depending upon the configuration.

Lights

Drivers of both the BMW M4 DTM and the BMW M4 Coupé can rely on the performance of modern LED headlamps. Light emitting diodes do more than simply save energy. Thanks to the significantly shorter reaction time compared to conventional filament lamps, the driver behind is given more notice when a driver in front of him is braking. And every fraction of a second counts on the racetrack. The light generated by LEDs is also very similar to sunlight, making it particularly easy on the eye.

Technical data
Chassis: carbon-fibre monocoque with integrated tank and steel roll cage; carbon-fibre crash elements on sides; carbon fibre crash elements on front and rear
Length/width/height: 4,775 mm/1,950 mm/approx. 1,200 mm
Tank capacity: 120 litres
Engine: 90° V8 aspirated engine, four valves per cylinder, 2 x 28.0 mm air restrictors (in accordance with regulations)
Capacity: 4,000 ccm
Output: approx. 480 bhp (with air restrictors, in accordance with regulations)
Max. torque: approx. 500 Nm
Engine management
system:
Bosch MS 5.1 engine control unit, central display
Transmission: Sequential 6-speed sports gearbox, operated via pneumatic shift paddles mounted on the steering wheel; 4-plate ZF carbon-fibre clutch; adjustable multi-disc limited-slip differential