• Connects a 1996-2004 Mustang Hydroboost with matching master cylinder installed with an MM Hydroboost Conversion Kit to the stock proportioning valve location.
• Will also connect to the MM Proportioning Valve Eliminator Kit.
• Direct fit installation; no cutting and flaring of brake lines necessary.

• Includes pre-bent hard lines.
• Correct tube nuts on the hard lines for each application; no separate adapters needed.
• T-fitting connects 2-outlet-port 1996-2004 master cylinder to 3-inlet 1987-1993 Mustang GT and LX brake system.

• MM Hydroboost Conversion Kits for 1996-2004 Mustang Hydroboost with matching master cylinder
• Stock 1987-1993 Mustang brake proportioning valve
• MM Proportioning Valve Eliminator Kit

• Any master cylinder other than the 4 listed
• 1993 Mustang Cobra
• 1979-1986 Mustang
• Hydroboost installation NOT using the MM Hydroboost Conversion Kit

See the Parts ID tab for photos to help identify your Hydroboost unit and master cylinder.

Important Fitment Notes
Production tolerances of Fox Mustangs are notoriously sloppy. In other words, while we love them, the cars weren't built to standards that MM deems precise. If you're into Fox bodies, you probably already know about this drawback in your favorite car.

When the MM Engineering Team installed our prototype Hydroboost Conversion Kit into several different Mustangs, they found significant tolerances that affected fitment. This discovery led to our engineers designing unique brake hard lines to make adjustment and alignment during installation as easy (and precise) as possible.

During installation of this kit, expect to make minor adjustments in the bends to align the tube nuts with the ports of your Hydroboost master cylinder and the brake proportioning valve (or use MM's Brake Proportioning Valve Eliminator Kit: MMBAK-6).

Brake hard lines are made from special tubing that's quite forgiving. It can be bent and straightened repeatedly by hand without damage. With our DIY customers in mind, MM created these brake lines with multiple bends separated by straight sections to allow adjusting each line to fit any situation.

The goal is to align the tube nut on each line end with the port it threads into. It's easy to do this, because there are more bends than necessary to position the nuts. The entire line acts like an accordion; each bend only needs to be adjusted by a very small amount to align the tube nuts, so no significant change needs to be made to any one individual bend.

The Mustang Hydroboost units and master cylinders can be difficult to tell apart. The photos below illustrate the differences between them. You need to know which Hydroboost unit and which master cylinder you have in order to get the correct conversion kit and brake line kit.

1996-1998 Master Cylinders


1999-2004 Master Cylinders