No, it wasn't the expense of the project, although that was probably considerable.
For years, rumors persisted that Alpina - the German auto manufacturer that specializes in building high-priced, high-performance versions of production BMWs - was going to have a crack at redeveloping BMW's i8 hybrid sports car. Those rumors were confirmed true back in July, when Alpina boss Andreas Bovensiepen spoke rather candidly with journalists about the cancelled project, sharing that the company even made it as far as building a functioning prototype.
So what, ultimately, sank the Alpina i8? It wasn't the outright expense of the project, as you might initially be inclined to believe, nor was it the fact that a higher-performance model might run counter to the i8's environmentally conscious image. More rather, it was the difficulty of calibration.
That's according to Bovensiepen himself, who recently spoke to BMW Blog about the canceled Alpina i8, and the difficulty surrounding the production i8's complicated powertrain, which uses a 129-horsepower motor on the front axle and a 220-hp turbo-three to drive the rear. Getting both of those powerplants to work together in concert, making for a well-balanced car, takes some doing. And Alpina's version of the i8, with a 350-hp turbo-four and an eight-speed automatic transmission in place of the old six-speed, contained so many changes that bringing the whole thing back into balance would have been hugely complicated.
Granted, the expense didn't help; switching from a 220-hp turbo-three to a 350-hp turbo-four necessitated a bespoke aluminum rear subframe, not to mention better cooling.
Alpina's prototype BMW i8 also ran with wider front tires and more camber than stock, in an attempt to dial out some of the production car's tendency for understeer, and that meant incorporating some wider fender flares. In the end, the Alpina car put out a healthy 455 hp and 516 lb-ft of torque, gaining around 220 pounds in the process. Taken altogether, the alterations were enough that Alpina would have had to subject its i8 to its own round of crash testing to meet regulations, which is an expensive and lengthy process in its own right.
It would have been a magnificent car, if only it had ever been finished.