SPL F8X M2/M3/M4 Rear Upper Arms (Rear Camber and Guide)

Rubber should be saved for the tires. The factory rear wishbone and guide links on the F8X use soft rubber bushings that flex every time you brake, turn or put power down. That movement lets the wheel and tire walk around, changes the alignment you worked so hard to dial in, and sends you chasing damper and setup changes that were probably right in the first place. SPL’s rear upper arms replace those links with fully adjustable, spherical bearing arms that keep the rear of the car locked in and repeatable on track.

Why these arms matter on the F8X

• Replaces the factory rear wishbone and guide links to give precise control over rear camber on F80, F82/F83 and F87 chassis.
• Wide adjustment range so you can hit proper track alignment specs or dial the car back for street use without fighting factory limits.
• Eliminates bushing deflection with smooth, Teflon lined spherical bearings instead of soft rubber, so the tire stays in the contact patch you aimed for.
• Motorsport style clamps keep the arm from “walking” when you tighten it, so the alignment you set on the rack is the alignment you get on track.
• High misalignment bearings provide plenty of articulation range and help avoid bind on lowered cars or cars with more travel.
• Allows small track width changes and fine tuning of the rear geometry when you start pushing wider tire and wheel packages.
• In our experience, these are effectively required hardware to reach the aggressive rear camber targets F8X and G8X cars like to run on track.

Motorsport hardware we trust

Like the rest of the SPL catalog, these arms are designed, machined and assembled in the U.S. from structural aluminum, stainless hardware and titanium fasteners. FK rod ends with Teflon linings keep friction and stiction low while holding up to real track mileage. They are easy to adjust in the shop or at the circuit and hold settings without drama, which is why we use SPL rear uppers on our own BMW M2, M3 and M4 builds.