The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

S197 3V Converting 2007 Mustang GT to Manual brakes for road racing? Thoughts?

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Exp. Type
Exp. Level
20+ Years
Pro built Spec Iron 2007 Mustang GT road race car. Drove the car for 2+ years in a multitude of track events with zero issues. Now constant brake problems -hard pedal. 2 master cylinders, 2 new boosters , lines, bleeds, rear calipers et al...even replaced the booster check valve with a steel one from Earls' with no fix. Car has 4 piston Brembos up front and OE sliders in rear.

Before I go medieval and go complete manual/prop valve on this car-What am I missing?

Thank you,

Exp. Type
Exp. Level
20+ Years
I'm not a brake expert by any means. But I do have experience with manual brakes on a track dedicated car.

When I converted my non ABS 944 turbo to LS1 power the brake booster had to be removed to make room for the motor. I had adapters fabricated so that I could run GT3 6 piston calipers in the front and retained the 4 piston calipers in the rear. I installed a wilwood proportioning valve on the dash which was dialed in and marked so it could be returned to the proper position after brakes were bled.

I ran Hoosier or Kuhmo scrubs.

The car was tracked in this configuration from 07 until I sold it in 14.

Once the proportioning valve was dialed in it took me very little time to get used to the brakes without the booster. I even went to a BMW master cylinder that was 1mm larger in diameter and there was no noticeable increase in force required.


TMO Supporting Vendors

Latest posts

Buy TMO Apparel

Buy TMO Apparel

TMO Vendor Posts