BMW has typically been more cautious about how many models get the full M treatment than, say, arch-rival Mercedes is with its prolific AMG models. But the lineup is expected to grow by at least one more in the near future.
That model is the highly anticipated X3 M – high-riding counterpart to the M3, top version of the forthcoming compact crossover, and baby brother to the larger X5 M and X6 M. And now we’re hearing rumors of what BMW will slot underneath the hood.
According to Autoevolution, the X3 M will be the first beneficiary of the new S58 engine. Replacing the S55 that powers the M3 and M4, the new S58 will be based on the B58 that appears in 40i models – from the M140i all the way up to the 740i.
Like the S55, the B58 is a 3.0-liter turbocharged inline-six. In its current form, it employs a single twin-scroll turbocharger, direct injection, variable valve timing, and a water-to-air intercooler to produce between 322 and 335 horsepower. The S58 on the other hand will have bigger shoes to fill: expect twin turbochargers in this application to produce upwards of 450 horsepower, surpassing even the M3 Competition Pack for output – and putting the current X3 xDrive35i with its 302 horsepower to shame.
From there the engine will be slotted into the next M3 and M4 – and for output levels to increase from there with more potent versions to follow.