Having a smaller and lighter engine than the AMG GLC 63 is a good start.
It’s a sign of the times that the engine powering the next BMW M3 will preview in an SUV rather than in the highly-regarded sedan and M4 coupe. This is an era, after all, where engines and platforms are being built as flexibly as possible to adhere to increasingly strict emissions and safety standards, so it's no surprise that the M Division is sharing such a great (and expensive to develop) engine with some of its SUVs. On the other hand, competition in the performance segment has never been more fierce, and BMW’s new X3 M and X4 M that the race for better lap times has made it to the SUV segment, too.
It's also why is reporting that BMW M president Markus Flasch thinks the X3 M and X4 M were developed as equals to the BMW M3 and M4, and aren't to be considered niche alternatives for daring soccer moms.
Starting with the same engine isn’t a terrible move when it comes to replicating the feel of an M3 and M4, and that holds especially true when the competition, the Mercedes-AMG , has a heavy V8 under the hood. "The advantage of our car in this segment is not just the more economical fuel consumption, but it's less weight in the front of the vehicle that makes the X3 M much more fun to drive than V8-driven cars, so I don't see a disadvantage there,” said Flasch. "I see an advantage on the performance and the fuel economy side.”
Given that the X3 M and X4 M both have 3.0-liter twin-turbo inline-six engines that make 473 horsepower in standard guise or 503 horsepower in Competition models - which puts the Bimmers in the same neighborhood of output as the GLC 63 and GLC 63 S - the weight saved by using a smaller engine could do wonders for handling given that it gives up no ground in terms of horsepower.
In fact, Flasch thinks the two M models will be so great that they’ll feel very . "We've found a way to not just put high-output engines in SUVs, but we've found ways to distinguish the character of these cars to basically give you... the driving dynamics based on sedans,” said Flasch. "This was also the target for the X3 and X4 M development. We didn't want to create just an M version of the X3, we wanted to create the M3 in an SAV ['Sports Activity Vehicle'] segment. I think we've achieved that goal and this is how we'll go forward. This is why SUVs are so relevant,” he added.
We know that the X3 M and X4 M’s engine, called "S58" in BMW speak, is 95-97% brand new and has been optimized to rev high and produce torque throughout much of the rev range. That means it shouldn’t have any trouble replicating the M3 and M4’s acceleration. Whether it will handle similarly in the real world remains to be seen.