The powertrain tie-up between Renault-Nissan and Daimler, parent company of Mercedes-Benz has already turned out talk of sharing between the two for a new small-sedan range, as well as the E-Class and Infiniti G/M sedans. Now the talk has turned to Nissan's next-generation Z sports car, potentially running with Mercedes-Benz power under the hood.

As it stands, that would actually mean a downgrade in power for the Z, which currently sports Nissan's 3.7-liter, 332-horsepower, 270 pound-foot V-6 engine. Mercedes-Benz's recently unveiled, revamped 3.5-liter V-6 generates 306 horsepower and 272 pound-feet of torque. But the rumors circulating now hint that the Z might not stick with gasoline V-6 power alone.

The 3.5-liter V-6 from Mercedes could be paired with the hybrid drive system found in the Mercedes-Benz S400 for an extra shot of power plus greener emissions. Other options include the V-6 diesel engine from the E-Class, plus a 221-horsepower, 420 pound-foot four-cylinder gasoline-electric hybrid due to make its debut in the upcoming Mercedes E300 Bluetec.

But that's not all: Mercedes' Diesotto engine is also rumored to be under consideration, which combines the high compression and sparkless ignition of a diesel with gasoline fuel under low loads, and switches back to regular spark-initiated combustion under full load. The technology has been in the works for several years now, with output rated at up to 238 horsepower and 295 pound-feet of torque from a 1.8-liter four-cylinder experimental engine.

The Nissan 370Z was just released for the 2009 model year, however, meaning it will likely be at least another four years before the next-gen Z arrives.

[Autocar]