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Founder, 1929-2014
Speedy Bill
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Compact Adjustable Proportioning Valve

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Outlet Fitting:
1/8" NPT
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Can also be used as a shut-off valve.
Compact Adjustable Proportioning Valve
Product Video
Compact Adjustable Proportioning Valve

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Watch the video below to learn more about the differences in brake lines, flare types and fittings you may want to consider before plumbing away on your current chassis project.



Q & A

What's in the Box

Very compact, can be hidden in cars that do not allow adjustable proportioning valves. Color reference scale on valve stem allows fast, accurate setting. Installs in rear brake line and allows you to adjust front-to-rear brake bias to prevent rear brake lock-up under heavy braking. 

  • Can be used as full shut-off valve
  • Rated to 2000 psi
  • Flows 3 gpm
  • Inlet:  1/8" NPT port
  • Outlet:  1/8" NPT port

Learn more about how adjustable proportioning valves work by reading our tech article. Brake System Selection.  


  1. Brake System Builder's Tip (Link)
  2. Valve is marked "MC" for the master cylinder end (fluid in) and "BR" for the brake end (fluid out).

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