BMW is currently testing the next-generation Z4 with an inline-six engine in two different power configurations, BMW Blog reports.

It is reported that the 3.0-cylinder engine is dubbed the B58M1 in standard guise and the B5801 in range-topping form and will power the M40i. The entry-level engine will deliver approximately 335 hp while the tweaked version is expected to have 385 hp on tap.

The reason for the different engine outputs is quite simple. The more powerful version will be built for countries without tight EU emissions regulations, including the U.S. Meanwhile, the 335 hp mill should be offered elsewhere.

As no new-age BMW Z4 M is believed to be on the cards, the M40i will be the most powerful Z4 offered to customers. Joining it will be a base 2.0-liter four-cylinder with about 180 hp and 200 lb-ft of torque and a slightly tweaked version with 248 hp and 258 lb-ft.

BMW recently previewed the new Z4 with a stunning concept at the Pebble Beach Concours d’Elegance.

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