Unacquainted with racing, but newly familiar with the M2 Racing that just got released? You’re probably wondering why BMW packaged the B48 inline-four with the race car as opposed to 3.0-liter six from the roadgoing M cars. After all, M stands for Motorsport, doesn’t it? The B48 four-cylinder isn’t even appear in any full M cars. As it turns out, BMW has perfectly valid and downright smart reasons for staying away from the S58 six-cylinder we know and love.
Why the M2 Racing Uses a Four-Cylinder Engine
So, what gives? Why would BMW M — ostensibly, the Motorsport division — opt to use a less exotic and arguably less powerful motor for a full-blown race car? The chief reason, for certain, is running costs. The B48 is easier and simpler to replace and repair parts on compared to the S58. In racing, breaking things comes with the territory. BMW says the M2 Racing “combines easy operability with low operating costs,” and a lot of that comes down to their decision to use the B48. The B48 is also lighter than the S58; and if you’re familiar with racing or going fast in general, that’s probably all you’ll need to read. The lighter engine also allows BMW to sustain their claim that the M2 Racing has been optimized for “performance, drivability, tire wear, and mileage.” Remember, in part thanks to BMW’s engine choice, the M2 Racing tips the scales at just 1,498 kg (3300 pounds); that’s around 500 pounds (226 kg) less than the streetcar.
Opting for the 2.0-liter engine also gives BMW racing fans more options. Remember, race events like the 24H Series and Dutch Supercar Challenge restrict cars based on engine displacement and/or aspiration. The M4 GT4/GT4 EVO already relies on a 3.0-liter mill. By bringing a new race car to market with a lower displacement engine, customers can now race in series that would have otherwise been off-limits to a BMW race car. That — combined with the lower price and reduced running costs — means BMW can sell more race cars. It also means more customers can get the opportunity to race. Talk about a win-win.
What Would BMW Have Gained With the S58?
The B48 also makes a ton of sense when you realize there is little gained by swapping in the S58 for any racing application. The S58 weighs more and power is generally restricted in each class. Generally, the M4 GT4 is already accomplishing anything that an M2 Racing with the S58 would’ve done. The M2 Racing is positioned as the grassroots factory race car. And the B48 was the perfect engine choice for that application.
