BMW M8 F91 Parts

The BMW M8 Competition Convertible - chassis code F91 - is one of the most technically sophisticated M cars ever built, and it doesn't get nearly enough credit in the enthusiast community. Sitting at the top of the 8 Series range, the F91 shares its bones with the F92 coupe and F93 Gran Coupe, but the open-top format gives it a character all its own. This isn't a car you buy because it's practical. You buy it because BMW took their GTE racing program seriously, filtered the knowledge down into a production convertible, and somehow made it work. If you've spent time with the older E63 M6 or even the F10 M5, the M8 feels like a generational leap - sharper, faster, and more willing to embarrass supercars that cost twice as much.

Every F91 sold in the US market comes in Competition spec, which means you're working with the S63M - BMW's 4.4-liter twin-turbocharged V8, producing 617 horsepower and 553 lb-ft of torque straight from the factory. This is not the same S63 you'll find in the F10 M5 or the E70 X5 M. The S63M received significant revisions for the M8: revised turbochargers, a new intake manifold, updated engine management, and a higher redline. It's a fundamentally stronger, more responsive unit. For context, the tuning community that cut its teeth on the N54 and S55 took notice immediately - this engine has headroom, and it responds to software in ways that should make the factory engineers nervous. A quality ECU tune from a reputable shop like Bootmod3 or MHD (where F-platform support has matured considerably) can push the S63M well past 700 whp on a stock hardware baseline. Add a set of upgraded charge pipes, intercoolers, and a fueling solution and you're looking at numbers that belong on a dedicated track build, not a convertible with a heated steering wheel.

No M car is without its quirks, and the F91 is no exception. The S63M's charge pipes - specifically the lower driver-side pipe - are a known failure point under elevated boost. This is an immediate priority upgrade for anyone planning to tune or push the car hard. Run the stock plastic pipes at your own risk; the aftermarket aluminum units from Burger Motorsports, Turner Motorsports, or Dinan are inexpensive insurance. The ZF 8HP automatic gearbox is genuinely robust, but if you're running a significant tune, an upgraded transmission fluid and heat management solution is worth the investment before you start dragging the car from a dig repeatedly. The M8's brakes are substantial from the factory - the optional M Carbon Ceramic package is excellent if you're doing track days - but even the steel setup benefits from a proper brake fluid flush and upgraded pads like Hawk HPS 5.0 for street duty or Pagid RSL29 if you're heading to a circuit. Don't overlook the cooling system; high-ambient track days will expose the limits of the factory setup, and an upgraded auxiliary cooling solution from Mishimoto or CSF is worth adding to your list early.

Suspension tuning on the F91 is a nuanced conversation. The factory Adaptive M Suspension is genuinely excellent for a grand tourer of this size, but it has predictable limits on track. The F91's convertible body means it carries more weight up high than the coupe, and you'll feel that in transitions. A quality coilover setup - KW Variant 3 or HLS4, or the Öhlins Road and Track system - transforms the car's composure without turning it into something you don't want to drive to dinner. Check out the full range of suspension options we carry for the F9x platform and pay attention to the endlinks and front control arm bushings while you're in there, as those wear ahead of schedule on cars that see any spirited driving. For wheel and tire fitment, the factory staggered setup works well but limits your tire rotation options; many track-focused owners move to a square setup with 285/30R20 all around on a lightweight forged wheel from Apex, HRE, or BBS to shed rotational mass.

The beauty of the F91 is that it responds well to both philosophies - refined daily driver or genuine track weapon - without necessarily forcing you to choose permanently. For street-focused builds, a tune, charge pipe upgrade, a valved exhaust system from Akrapovič or Eisenmann, and a wheel swap gets you into genuinely serious performance territory while keeping the car civil on a commute. The factory exhaust is quiet enough to irritate you after a tune; the Akrapovič Evolution system in particular transforms the S63M's soundtrack into something properly theatrical. For track builds, layer in the coilovers, brake package, cooling upgrades, and a proper aero solution - the M Performance front splitter and rear spoiler lip are surprisingly effective, or go further with one of the carbon front lip and diffuser packages in our Body & Aero section. At the end of the day, the F91 M8 Competition is one of those platforms that rewards owners who take the time to understand it. The factory engineers gave you an exceptional foundation. The aftermarket is ready to help you build on it.