BMW may have ended production of the Z4, but the roadster isn’t quite ready to disappear. The family behind one of BMW’s most famous performance partners has found a way to keep it alive, albeit in a significantly more exclusive form.
Bovensiepen has revealed the Spider, a two-seat roadster based on the departed Z4 M40i. The company is run by the family that founded Alpina, which BMW acquired after decades of producing faster, more luxurious interpretations of its cars.
The Spider follows a familiar philosophy. Rather than radically reinventing the Z4, Bovensiepen has increased its performance, sharpened the chassis, redesigned several exterior elements, and upgraded the cabin.
There’s a catch for anyone who missed their opportunity to buy a new Z4: the Spider starts at €115,500, equivalent to roughly $134,000. Production is also limited to just 99 hand-built examples.
The Z4 Now Has 429 HP
Under the hood there’s still a turbocharged 3.0-liter inline-six, although Bovensiepen has given it some additional breathing help. A revised intake with an additional ram-air channel, an enlarged intake silencer, and a freer-flowing sports exhaust help increase output.
The result is 429 horsepower (435 PS) and 428 lb-ft (580 Nm) of torque. Bovensiepen claims 0-62 mph takes 4.2 seconds, while the standard top speed is 162 mph.
An optional Performance Package raises that ceiling to 183 mph. It adds a milled aluminum differential cover with larger cooling fins and an underbody V-brace designed to increase structural rigidity.
Unfortunately for manual enthusiasts, the Spider is available exclusively with an eight-speed automatic, so you won’t be rowing your own gears.
Frank Stephenson Helped Redesign It
Former Ferrari and McLaren designer Frank Stephenson collaborated with Bovensiepen on the Spider’s exterior components. The transformation is subtle enough that its Z4 origins are obvious, although several details distinguish it from the BMW.
Changes include new front-fender vents, a gloss-black splitter, redesigned side skirts, a more aggressive rear diffuser, and a larger rear spoiler. Special 20-inch forged wheels wrapped in Michelin Pilot Sport 4S tires complete the look.
Bovensiepen also retuned the dampers and fitted longer auxiliary springs at the rear. Buyers can add a high-performance braking system with four-piston front calipers and larger perforated discs.
Luxury Comes At A Price
Inside, the Spider receives Vernasca leather and Alcantara upholstery, while its heated steering wheel is wrapped in Bovensiepen’s upscale Lavalina leather. Customers willing to spend even more can cover additional sections of the cabin in leather or Alcantara.
Deliveries are scheduled to begin in the first quarter of 2027. With only 99 planned, the Spider isn’t really a replacement for the Z4 so much as an exclusive farewell to the formula.
At roughly $134,000 before getting carried away with personalization, it’s certainly an expensive way to keep the Z4 alive. For buyers who always wondered what an Alpina-flavored BMW roadster might have been like, however, the Spider comes remarkably close.