Bovensiepen, the successor to the original Alpina company, has introduced its latest project: the Bovensiepen Spider. This modified BMW Z4 retains the classic front-engine, rear-wheel-drive layout while receiving significant mechanical and aesthetic enhancements. Under the hood, the 3.0-litre inline-six turbo engine has been tuned to produce 430bhp and nearly 430lb ft of torque. This represents a notable increase over the standard model’s 355bhp and 369lb ft, with power routed through an eight-speed automatic transmission.
Performance figures show a 0-62mph time of 4.2 seconds, an improvement over the stock 4.5 seconds. When equipped with the optional Performance Pack, the top speed climbs to 183mph. The engine upgrades include an “unrestricted” air intake duct with a ram air channel, a larger intake silencer, and a bespoke exhaust system designed to reduce back pressure while delivering a “sporty” and “bass heavy” exhaust note. Cooling has also been optimized to support the increased output.
The chassis has been refined with tuned dampers featuring increased compression at low speeds, longer auxiliary rear springs, and an optional high-performance braking system with four-pot calipers. The Performance Pack further enhances the vehicle’s structural rigidity with an underbody V-brace and a rear aluminium differential cover equipped with larger cooling fins.
Externally, the Z4 has been restyled by Frank Stephenson, the designer behind the McLaren P1. His modifications include a new front splitter, side skirts, a rear diffuser, a rear spoiler, and 20-inch lightweight forged alloy wheels. Inside, the cabin features extensive leather and Alcantara upholstery, with broad customization options available to buyers.
Bovensiepen plans to limit production to just 99 units of the Spider. Pricing for the vehicle starts at €115,500, with customer deliveries scheduled to commence in 2027. The report also notes that indeed, Bovensiepen’s upped the power from BMW’s long-serving 3.0-litre inline turbo, here delivering a very healthy 430bhp and just under 430lb ft – more than the standard car’s 355bhp and 369lb ft, you’ll note – via an. The report also notes that mind, that time now 4.2s instead of 4.5s, but the top speed with the Performance Pack fitted rises to 183mph, only a few tenths quicker to 62mph.