Michael Wimbeck – project manager for the new BMW Z4 – was unequivocal when asked whether the previous model had provided any inspiration for the new roadster: "No, we didn't take any inspiration from the previous model," he said.
Co-developed with Toyota, the plan, according to BMW engineers, is that Toyota will offer the Supra only as a coupe, while BMW will offer the Z4 only as a roadster. If you've read our reports on the Toyota Supra on CarAdvice, you'd know that the Japanese manufacturer has stated there would be no Supra without the co-development synergy with the Bavarian manufacturer.
"The car is 100 percent BMW, the tuning of the engine, suspension and gearbox, the electronic adjustments are made for BMW," Wimbeck told Australian journalists. "The Toyota is BMW engineering with Toyota design and application even though we both had nearly the same aim with the car. The segment sales figures have dropped, and Z4 probably wouldn’t exist without Toyota."
Like most BMW sports applications, the Z4 roadster needed to be a multi-faceted sports car, just as capable of daily driving duties as it is a rapid track blast, evidenced by its Nurburgring lap time. While lap times don't necessarily resonate to the average buyer, they do, according to BMW, illustrate the outer capabilities of their vehicles.
"The new Z4 is a real sports car, that’s what the time at the Nurburgring was all about, and it has all the goods that BMW has at its disposal," Wimbeck explained. "It was the first non 'M' car to go under eight minutes and our internal benchmark was the M240i. Through the development phase though, the Z4 got better and and better, and the M240i wasn’t good enough anymore. So we took the M2 as our benchmark."
BMW engineers spent a lot of time and resources in the planning phase ensuring the Z4 had a rigid body structure, deliver on 50:50 weight distribution, with the use of lightweight components up front, such as the aluminium hood and quarter panels. Still, it's no stripped out lightweight either.
"We believe it has perfect steering feel, with the 1610kg overall weight," Wimbeck said. "There will be a four-cylinder version that is 100kg lighter and we reintroduced the manual to have a more affordable offering. The manual was not really to do with demand. The number of people who want it is very little, so little."
The duality of character required was crucial to the appeal of the Z4 according to Andy Ederer - product manager for Z4.
"We wanted this car not to just be good for cruising on Sunday afternoons, but for empty roads on a Sunday morning," Ederer said, "It used to have disadvantages in terms of acoustic comfort, and in terms of temperature, but those disadvantages are no longer there because the development for the canvas tops is so much better now."
Was a hardtop considered for Z4 at any stage? "No, not this time," Ederer said. "Weight, centre of gravity, the same trunk volume open or closed (280 litres), while the retractable hardtop takes up a lot of space, canvas is a very big advantage."
According to BMW, the canvas top resonates historically too, in that it is true to the concept of the roadster in its original form. "We thought that the canvas top was the solution," Ederer said.