Knob Style Proportioning Valve

The Knob Style Proportioning Valve by BAER BRAKES (SKU BAE2000035) is a critical component for custom and performance brake systems where independent pressure modulation is essential. This adjustable proportioning valve lets you fine-tune brake pressure distribution between front and rear circuits, preventing rear-wheel lockup during hard braking and improving stopping consistency on custom-built or modified vehicles. Whether you're upgrading an older vehicle with modern braking technology or dialing in a high-performance street car, this valve gives you manual control over brake bias—something drivers upgrading from stock systems often discover is non-negotiable for safety.

Engineered from lightweight aluminum, this proportioning valve features dual 3/8-24 inch inverted flare female ports for both inlet and outlet connections, making integration straightforward in most custom brake line applications. The knob-actuated design allows real-time adjustment across a 100–300 psi pressure range, giving you precise control without requiring in-line tools or line access. The inverted flare connection style is industry-standard for hydraulic brake systems and ensures reliable, leak-free sealing when properly installed with quality brake hose and fittings. Its compact footprint (3 x 2.5 x 4 inches) fits neatly in engine bays, under-dash installations, or trunk-mounted proportioning setups common in custom brake builds.

This valve is ideal for builders upgrading drum-brake equipped vehicles to disc systems, restomod projects mixing classic chassis with modern hydraulics, and track-focused street cars requiring bias adjustment for different weight distributions or tire compounds. Professional mechanics and serious DIY enthusiasts benefit from the knob control, which eliminates guesswork and allows fine-tuning after test drives. Installation requires standard brake line wrenches (typically 9/16" for 3/8-24 inverted flare fittings) and should include a full system bleed to remove air and ensure predictable pressure response. Always verify rear brake saturation before and after valve adjustment to confirm that rear-wheel lockup is eliminated across your intended braking range.