Whereas the i8 leaves the factory with a 1.5-liter three-cylinder turbocharged engine sourced from a Mini, Alpina decided to ditch this engine and replace it with the same 2.0-liter turbocharged four-cylinder as the BMW M135i. This engine was then coupled to electric motors that brought combined grunt up to 462 hp and 516 lb-ft (700 Nm) of torque.
Speaking with BMW Blog, Alpina boss Andreas Bovensiepen has revealed all the various issues the company encountered when developing the car.
For starters, cooling was an issue and not only did Alpina have to replace the standard intercooler with a larger one but it also had to fit two additional intercoolers in the front fenders to cool the oil and the transmission.
In addition, Alpina discovered that the i8’s standard six-speed automatic transmission couldn’t deal with the extra power, forcing it to fit the same eight-speed Aisin auto as the M135i. This new gearbox, as well as the larger engine, also required Alpina to create a new rear subframe that was stronger than the standard one. The Alpina i8 also gained at least 220 lbs (100 kg) of weight and would have needed to be crash-tested, presenting yet another hurdle for the company.
As noted by BMW Blog, the biggest challenge for Alpina to bring the car into production related to the software calibration. As the standard three-cylinder had been replaced, Alpina needed to re-calibrate all of the software to work with the four-cylinder, a process that was time-consuming and expensive. The company then decided it wasn’t worth proceeding with the project.
This version of the story slightly contradicts an earlier report from 2019 on the matter, when Bovensiepen told Jalopnik that the main reason their four-cylinder i8 never saw the light was BMW themselves, who asked Alpina to shut down the project in fear of diluting the BMW i’s eco-friendly brand identity.