AP Racing Radi-CAL Competition Front Kit 9668 - F87 M2, F80 M3, F82 M4

This AP Racing by Essex Radi-CAL Competition Brake Kit gives the BMW F87 M2, M2 Competition, F80 M3 and F82 M4 a front brake system sized for long track days. It uses AP Racing CP9668 Radi-CAL Pro5000R six-piston calipers, the version of the Radi-CAL body that takes a 25mm thick pad, clamping 372 x 34mm two-piece J Hook discs. Owners who burn through pads quickly at the track get far more pad material per set than the factory 18mm pads offer.

Why upgrade

Compared with the M2 Competition front brake package, the kit saves about 24 pounds of unsprung weight, and roughly 8 pounds against the standard iron brakes on the M2, M3 and M4. Each caliper weighs 6.9 pounds without pads and each disc 21.4 pounds, versus 30.4 pounds for the M2 Competition disc. Lighter corners mean quicker turn-in and better tire contact over curbs, and pistons are sized to work with the OEM master cylinder and ABS, so the pedal and stability systems feel familiar.

Caliper and disc construction

The CP9668 Radi-CAL caliper uses an asymmetric body that puts material only where braking loads travel, finished in hard anodizing that does not chip at temperature. Stainless pistons keep heat out of the fluid, anti-knockback springs hold the pedal firm, and the thick pad shape is offered by all major pad makers. The CP7177 discs carry 72 vanes and ride on 6061 hard anodized aluminum hats with fully floating hardware, which lets the iron ring grow with heat without distorting.

Features

• AP Racing CP9668 Radi-CAL Pro5000R six-piston calipers with 25mm pads
• 372 x 34mm, 72-vane J Hook discs on floating aluminum hats
• Saves 24 lb vs. the M2 Competition brakes and about 8 lb vs. standard iron
• Fits inside popular 18 inch track wheels
• Works with the OEM rear brakes or a matching AP Racing rear kit

What's Included

• One pair AP Racing CP9668 Radi-CAL Pro5000R six piston calipers
• One pair 372x34mm AP Racing CP7177, 72 vane, J Hook racing discs, with fully floating 6061 hard anodized aluminum hats, and attachment hardware
• One pair caliper mounting brackets and hardware
• One pair Spiegler Stainless Steel Brake Lines with abrasion resistant coating
• Detailed installation instructions

Brake pads are not included.

Specifications

Video

Fitment notes

Fits the M2, M3 and M4 below. The OEM 437M 19 x 9 inch wheel fits with a 5mm spacer, and many 18 inch track wheels from APEX, BBS, BC Forged, Forgeline and Klassen fit without one; check other wheels with the wheel fitment template. F83 M4 Convertible and G8x models are not covered. For a lighter caliper with an 18mm pad, see part 13.01.10045.

Fitment