Realistic racer

How the virtual version of the BMW M4 GT4 is made

After six months of intensive development work, the BMW M4 celebrates its virtual premiere on the sim racing platform iRacing. In this story, we show how the virtual version of the racecar is made.

The digital experience of the real vehicle’s design and feel should be as authentic as possible. That’s why the developers of the iRacing BMW M4 GT4 worked intensively with BMW Motorsport engineers.

Developers need three things for the true-to-life sim racing BMW M4 GT4: laser scans, photos of the vehicle, and its CAD data – large, sensitive data packages with all original parts specifications.

Finally, another package provides info on BMW Motorsport driving dynamics, including M4 GT4 damper curves, engine performance curves, axle kinematics, weight distribution, and aerodynamic values.

To create a complete virtual vehicle from these data packages, the developers first parse the supplied data and use it to produce a basic model. Special attention is paid to the racecar’s proportions.

Using a complex process, iRacing has made a complete scan of the original BMW M4 GT4. With this precise data acquisition, the developers ensure that the outer appearance is identical.

In addition to the external appearance, driving dynamics and the finest of details like wiring in the interior, light and texture of the dashboard, as well as rotating wheels or display indicators are crucial for a realistic appearance, making the virtual experience even more authentic.

To implement these details, BMW Motorsport has even given the developers insights into which steering wheel lights turn on in which situations and which signals are shown on the display.

And there’s another parallel between real racecars and sim racing: At the end of the development period, the virtual vehicle is approved by BMW Motorsport. The BMW M4 GT4 is race-ready!