Alpina takes the direct-injection, twin-turbo, 3.0-liter BMW inline-6, substitutes forged Mahle pistons to pump the compression ratio up to 9.4:1 and then remaps the electronics. Maximum boost of 16 psi produces 355 hp between 5,500 and 6,000 rpm and 369 pound-feet of torque between 3,800 and 5,000 rpm.

The short answer revolves around the advantages that can be wrought from the direct-injection technology of the 335i's engine. For more than a year, Alpina's engineers refined the engine map to accept a man-sized dose of forced induction from the two turbos. The result? A massively broad power band like a large-capacity V8, but with the advantages of a lightweight and noticeably thriftier straight-6.