Wilwood 140-14980 FNSL4R Big Brake Rear Kit (Race), 12.88″ — BMW E46 M3 2001-2006

Wilwood 140-14980 FNSL4R Big Brake Rear Kit (Race) – BMW E46 M3

Wilwood’s complete Forged Narrow Superlite 4R (FNSL4R) big brake rear kit (P/N 140-14980), engineered as the rear-axle companion to the 140-14978 AERO6-ST front kit for 2001–2006 BMW E46 M3 models running in dedicated road race competition. The kit bolts to the factory OEM rear end location and is built to restore front/rear brake balance and heat capacity once the front axle has been upgraded to a big brake package — running the stock rear brakes behind an AERO6-ST front kit will overwhelm the rear’s stopping power and heat capacity long before the fronts fade. Requires 17-inch or larger wheels; always check the wheel clearance diagram before ordering.

The kit pairs FNSL4R-ST four-piston radial-mount calipers with a forged aluminum body and Type III hard anodized finish for wear and corrosion resistance in the piston bores. Thermlock® pistons reduce heat transfer from the pads to the caliper body, fluid, and seals, extending fluid and seal life and improving pedal consistency under sustained track use. Spec-37 alloy 12.88″ GT 48 curved-vane, GT slotted directional rotors mount to forged aluminum, black e-coat Dynamic Mount hats. The system is completed with high-temperature, high-friction BP-35 race compound pads (7416 plate, .65″ thick) and stainless steel braided flexlines, bleed screws, and hat mounting hardware — everything needed for a complete rear axle installation.

Specifications

Kit Contents

• 2 x Caliper – FNSL4R-ST, 4-Piston, Radial Mount (universal L/R): 120-12602
• 2 x Rotor – GT 48 Curved Vane, Spec-37 Iron, 12.88″ x 1.10″: Left Hand 160-12962, Right Hand 160-12961
• 2 x Rotor Hat – Dynamic Mount, Short Offset: 170-14979
• 1 x Brake Pad Set – BP-35, 7416 Plate: 150-35-7416K
• 1 x Flexline Kit – Stainless Braided, Rear: 220-14759
• 1 x Hat Bolt Kit – Dynamic Mount, 12-Bolt with T-Nut Tool: 230-6656
• 1 x Bleed Screw Kit, 4-pack: 220-0627

Fits

• 2001–2006 BMW E46 M3 (rear axle, OEM rear end). Designed as the rear-axle companion to the 140-14978 AERO6-ST front kit — see that listing for the matching front brake package.