The big luxury automakers have been engaged in a power war for decades now. Jaguar gave its 1990s XJR 370 horsepower so BMW made a 400-horse M5. Merc and Audi went better than that so BMW made a 500-hp M5. Since then we've seen forays well into the 500s and more, and now the same battle is happening in the world of four-cylinder motors.

Mercedes-Benz kicked off the latest craze with the A45 and CLA45 AMG—all two liters and 355 horsepower of it. It's the world's most powerful four-cylinder production engine, but it didn't take long for Volkswagen to respond, with rumors of a production, 400-horsepower version of the Golf R. Drive now reports that Mercedes-AMG is planning to offer more power still—defending its position as makers of the punchiest four-pot on the market.

AMG’s product planning manager Oliver Wiech denies that recent sightings of a wide-arched A45 hint at a Black Series model, but confirms the German firm will continue to develop its four-cylinder over time.

"We went into the segment with a plan," he told Drive, "and not with a single spot just to come in and let see what happens." He adds that right now, AMG is "on top", and the company intends to stay there in the future.

Given the advances in small engine technology and turbochargers, plus demands for more efficient road vehicles, could four-cylinder engines take over from super sedans and hypercars as the power war of choice?


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