brakes.jpg (3604 bytes) Brakes

My Objective

  1. the shortest possible braking distance
  2. straight stops
  3. good brake pedal modulation
  4. high reliability
  5. long brake pad and rotor life

The Plan

Front Brakes

Upgraded to 10.9" rotors and dual piston calipers from a scraped 1992 Turbo Legacy sedan. A no-nonsense bolt on and bleed brake fluid operation. Outback, 2.5GT, Impreza 2.5RS and Forester are equipped with 10.7" rotors and dual piston calipers. There is no significant performance difference between 10.7" and 10.9" rotors.

Upgrading to the larger brakes requires at least 15" wheels to clear the calipers. This winter I will reinstall my 10.2" rotors and single piston calipers to give me one more winter on my 14" snow tires.

Rear Brakes

Upgraded to 10.5" ventilated rotor and wide single piston caliper, also from the 1992 Turbo Legacy sedan.

Brake Pads

Using stock Subaru pads for now, may upgrade to Mintex pads at some point but I don't think they are needed. I have used aftermarket pads and found them to be too hard and weak when cold, which is not good when you have a deer jump out in front of you on the highway. Subaru pads are organic, and they work well when cold and hot.

Brake Booster

All North American Subaru's suffer from a soft brake pedal. This is due to the use of a dual stage brake booster. The second brake boost stage is activated too soon in the brake pedal stroke and makes light braking hard to modulate.

There is a four stage process to increase the pedal firmness and improve modulation:

  1. Adjust the brake pedal linkage. On the brake pedal there is a threaded rod that connects to the brake booster on the engine side of the firewall. Increase the length of this rod by turning it counterclockwise (clockwise when sitting in the driver's seat). Increase the rod length until the brakes begin to drag (test this with HOT brakes!), and then shorten the rod slightly until the brakes no longer drag.
  2. switch to the single stage brake booster, available from SPD
  3. install the brake master cylinder brace from MRT Rally
  4. install stainless steel brake lines

Current Status

Brakes are installed, brake booster has been adjusted.

The Results

Braking distance from 60MPH is down to 131 feet from 158 feet (according to a G-Tech), may I remind you that the Porsche Boxster requires about 145 feet to stop from 60MPH! The brake pedal is much firmer and modulation is easier. No more work required on the brakes.