Wilwood Adjustable Proportioning Valve Silver — Fine-Thread Knob, 100–1000 PSI Precision

Wilwood 260-8419 is a compact, forged-billet adjustable proportioning valve with a fine-thread knob that lets you precisely meter brake line pressure between 100–1000 PSI.

Engineered for performance vehicles and track-driven street cars, this next-generation proportioning valve delivers strong construction, a wide adjustment range and very fine control for dialing front/rear braking balance. The compact, lightweight design mounts easily in tight engine bays or behind panels, and it ships with inverted-flare fittings to work with most domestic hard brake lines. This description explains what it does, how to use it, and why its features matter when you need repeatable, adjustable braking response.

How does the knob let me adjust brake balance on the fly?

The finely threaded adjuster knob converts small turns into predictable pressure changes, allowing gradual decreases to rear-line pressure so you can tune bias without swapping components. Adjustment covers 100–1000 PSI with up to a 57% maximum reduction in line pressure, giving a broad window for setup.

• Fine-thread knob for precise incremental changes
• Pressure span from 100 to 1000 PSI for coarse or subtle tuning
• Maximum 57% pressure reduction available for rear-line adjustment
• Repeatable settings useful for track sessions or load changes

What fittings and ports does the valve use, and will it fit my lines?

The Wilwood valve features standard 1/8-27 NPT inlet and outlet ports and includes two adapter fittings that convert to 3/8-24 inverted-flare female. Those adapters are compatible with most domestic 3/16" hard brake lines right out of the box, simplifying installation.

• Standard 1/8-27 NPT inlet/outlet ports
• Includes two 1/8-27 NPT to 3/8-24 inverted-flare female fittings
• Works with most domestic 3/16" hard brake lines without custom adapters
• Compact footprint and two .25" side mounting holes spaced 1.00" for flexible placement

How durable and compact is the 260-8419, and where can I mount it?

Built from forged billet aluminum, the valve balances strength with low mass—just 5.2 ounces—making it suitable for tightly packaged engine compartments or behind interior panels. Two 1/4" side mounting holes spaced 1.00" apart provide a secure mounting footprint that fits many street and race installations.

• Forged billet construction for strength and longevity
• Lightweight: 5.2 ounces for minimal added weight
• Two .25" side mounting holes spaced 1.00" for secure attachment
• Compact form factor suited to tight or concealed installations

How precise is the pressure control, and what performance scenarios benefit most?

The valve’s adjustment range and fine-thread control make it ideal when you need repeatable braking bias: testing on track, matching brake feel after hardware changes, or tuning for varying loads. It doesn’t change braking system fundamentals but lets you proportionally reduce rear-line pressure to achieve desired balance.

• Precise metering helps tune front/rear bias across conditions
• Useful for drivers who alternate between street and track setups
• Helps compensate for differing pad compounds or rotor sizes
• Provides quick, reversible adjustments without replacing parts

Who is this for: Drivers and builders who want a compact, high-control proportioning solution—race teams, performance enthusiasts, and anyone fine-tuning brake bias. If you need dependable, repeatable pressure adjustment with straightforward installation and durable construction, the Wilwood 260-8419 offers a practical, tunable way to optimize braking balance without resorting to more invasive system changes.