Project Mu FS4M 4POT Front BBK 315x30mm for 2013+ FRS/BRZ/86 2022+ BRZ/GR86
Regular price
$2,895.00
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OVERVIEW
Strengthen front stopping capability and improve brake pedal feel with the Project Mu 4POT FS4M Street Forged Front Caliper Kit for 2013+ GR86 / BRZ / 86 / FR-S (ZN6/ZC6/ZN8/ZD8). Designed specifically for street enthusiasts and weekend canyon drivers, the FS4M features a compact forged aluminum body housing 38mm pistons. By pairing this rigid 4-piston caliper with 315mm x 30mm 1-piece round 6-slit rotors, Project Mu achieves high-performance thermal capacity while retaining clearance for most OEM and aftermarket 17-inch wheels. It serves as an accessible entry into forged aluminum brake upgrades without requiring aggressive wheel offsets.
| Caliper Feature / Spec | FS4M Street 4POT | FS44S Slim 4POT | FS44 Full-Size 4POT (345mm) | FS44 Full-Size 4POT (355mm) |
|---|---|---|---|---|
| Axle Position | Front Axle Specific | Front Axle Specific | Front Axle Specific | Front Axle Specific |
| Caliper Profile & Width | Compact Street Body (275.0mm L x 144.5mm W) | Slim Body (140.2mm Width - High Spoke Clearance) | Standard Full Body (156.25mm Width - Heavy Duty) | Standard Full Body (156.25mm Width - Heavy Duty) |
| Piston Diameter / Pad Layout | 38mm Pistons x 4 (2-Pads per Caliper) | 38mm Pistons x 4 (4-Pads per Caliper) | 41mm Oversized Pistons x 4 (4-Pads per Caliper) | 41mm Oversized Pistons x 4 (4-Pads per Caliper) |
| Rotor Specs & Thickness | 315mm x 30mm (1-Piece Round 6-Slit) | 355mm x 28mm (2-Piece Straight 8-Slit) | 345mm x 32mm Heavy-Duty (2-Piece Straight 8-Slit) | 355mm x 32mm Heavy-Duty (2-Piece Straight 8-Slit) |
| Target Application | Street Performance / Canyon & OEM 17" Wheel Friendly | Street & Track with Tight Wheel Clearance | Heavy-Duty Circuit / 17"+ Wheel Friendly Track Day | Heavy-Duty Circuit / Maximum Heat Mass (18"+ Wheels) |
FEATURES
- Compact Forged Caliper Body: Lightweight forged aluminum alloy structure provides high pedal response and rigidity without excessive weight.
- 38mm 4-Piston Architecture: Sized for street and spirited driving to maintain factory master cylinder hydraulic proportioning.
- 315mm x 30mm Vented 1-Piece Rotors: Cost-effective 1-piece round 6-slit rotors provide enhanced thermal management over stock rotors while retaining 17-inch wheel fitment.
- Round 6-Slit Face Design: Degasses pad friction material and maintains clean pad surfaces for consistent initial bite.
- Integrated Dust Seal Protection: Features dedicated outer dust seals in front of the main oil seals to guard internal hydraulics against road debris and dust.
WHAT IS INCLUDED
- 2x Project Mu FS4M Forged 4-Piston Front Calipers (Signature Teal Finish)
- 2x Project Mu 315mm x 30mm 1-Piece Front Brake Rotors (Round 6-Slit)
- 4x Project Mu Performance Front Brake Pads (Standard NS-C Compound)
- 2x CNC Machined Caliper Mounting Brackets & Hardware
- 2x Stainless Steel Braided Brake Lines with Teflon Inner Core
- Complete Set of Installation Bolts & Hardware
PART NUMBERS
- Manufacturer Part Number: FS4M-F103SP
SPECIFICATIONS
- Position: Front Axle
- Caliper Type: Forged Aluminum Compact 4-Piston (FS4M)
- Piston Diameter: 38mm x 4
- Caliper Dimensions: Length: 275.0mm | Width: 144.5mm | Height: 71.6mm
- Rotor Dimensions: 315mm Diameter x 30mm Thickness (1-Piece)
- Rotor Venting / Slits: Vented with Round 6-Slit Pattern
- Standard Included Compound: Project Mu NS-C (Optional: TYPE PS or D1 spec ZERO)
- Finish: Hard Anodized + Signature Teal Powder Coat
FITMENT
- 2022+ Toyota GR86 (ZN8) & Subaru BRZ (ZD8)
- 2013-2021 Toyota 86 / Scion FR-S (ZN6) & Subaru BRZ (ZC6)
- *Fits most OEM and aftermarket 17-inch or larger wheels
DISCLAIMER
- Backplate Processing Required: Installation requires trimming or modifying OEM front brake dust shields/backplates.
- Non-Affiliation & Warranty: Direct parallel import of authentic JDM components. We are an independent retailer, not an authorized Project Mu dealer. Factory warranty applies in Japan only.
- 14-Day Defect Window: Customers must inspect all parts upon arrival. Defect, damage, or missing part claims must be reported within 14 days of delivery and prior to installation. Installed items are non-returnable.
- Installation: Manuals are in Japanese. Professional installation by a certified technician is required.