The fifth-generation Supra will borrow additional hardware from the new Z4 roadster.

The road to the car's official reveal has been painstakingly long and we are still a few weeks away from the A90's debut in Detroit. When it will arrive at NAIAS, under the hood of the fifth-generation Supra there's going to be a BMW engine. In an interview with Automotive News Europe, chief engineer Tetsuya Tada explained the reasoning behind the decision to source the heart of the Supra from another automaker.

When Toyota decided to dust off the legendary "Supra" moniker by approving a new sports car, the first order of business was to secure a straight-six engine. Why? Because customer surveys showed that was a must considering all four previous generations of the car had an inline-six. The easiest way to obtain one was to ink a deal with BMW and grab their 3.0-liter you'll find in the Z4 M40i as well as in the new M340i. Toyota decided against developing its own straight-six, which although did upset purists, it's a business move that makes sense considering the Supra won't be a high-volume car.

The engine of Bavarian origins has been tuned by Toyota's engineers specifically for the Supra, as it's the case with other BMW-sourced vital hardware, such as the eight-speed transmission and the chassis. Despite sharing more than a few parts, the two companies have promised distinct identities for their sports cars that will go well beyond the different body style. Having seen the new Z4 and a revealing image of the Supra, we know for sure their exterior designs won't have anything in common.

Getting back to the interview held at a track southwest of Tokyo during a test drive event, Tada hinted future Gazoo Racing models will use engines developed by Toyota's go-faster division. These will be all-new engines rather than more powerful configurations of existing units, and will likely support electrification for extra boost and lower emissions.