Description
This big brake adapter kit allows you to use the OEM F80 M3/F82 M4 Brembo Calipers and 380x30mm rotors on your non-M E8x or E9x. This kit includes everything you need, including special fasteners. Does not include stainless steel hoses, but are recommended (
ES#3612570)
Part Numbers:
- Calipers: 34116799469 and 34116799470. Found on F30's, F80, and F82's.
- OEM Rotors: 34112284810 and 34112284809
As with everything Seems Legit makes, this kit is designed (including FEA) and manufactured here in the USA. They are CNC machined from billet 4140 steel, gold zinc coated, and have a safety factor of 6 so they are prepared to take whatever you can throw at them.
Critical to designing a big brake kit is not only the "bigger is better" mentality, but piston size, rotor torque, and brake bias which are all important primary factors. Without changing your brake booster or master cylinder this kit changes your brake bias by less than 1%. This ensures that the vehicle will retain a good initial bite, balance, and will have consistent pedal travel just like OEM.
The M3 & M4 calipers are a lightweight 2-piece design with stainless steel pistons. The stock 135i 6-pot Brembo is notorious for having the ceramic pistons crack after only a few track sessions. Even after you spend a bunch of money on new pistons and seals, the OEM brakes still have trouble slowing down these vehicles with just a small 338mm iron hunk they try to call a rotor that does not shed heat well. With this kit you are adding over 40mm of surface area of the rotor and using an aluminum rotor hat which cools down dramatically faster. On top of that this is still cutting weight from the system. See list of weights below. A potential loss of 2.4 pounds per corner of unsprung mass, while increasing the braking potential greatly. Truly a win/win upgrade.
Weights:
- 135i Brembo Caliper – 11.4lbs
- 135i Rotor – 22.5lbs
- M3/M4 Caliper – 10.7lbs
- M3/M4 OEM Rotor – 24.8lbs
- M3/M4 Stoptech Trophy Aerorotor – 23.8 lbs
- M3/M4 Racing Brakes Rotor- 19.9lbs
Wheel Requirements:
- Wheels must have barrel of 17" or greater to clear this setup. Fits most 18" wheels.
Instructions:
- Remove brake hoses either at the caliper if you are reusing the original hoses or at the body if installing new hoses
- Remove original calipers and rotors
- Clean knuckle assembly of dirt and loose rust
- Install brackets to each caliper using the Zinc-Coated Allen Head screws and red Loctite: Torque to 70 ft/lbs
- Install 380mm F8X M3/4 rotor using the included security fastener
- Bolt caliper and bracket assembly to the knuckle using the included flanged hex-head bolts and washers: Torque to 70 ft/lbs
- Attach brake hose and bleed brakes