Distribution Block w/ Proporti

OVERVIEW

When you are building a high-performance air-cooled machine, whether it is a street-pounding Cal-Look Beetle or a rugged off-road sand rail, your braking system is the most critical safety component you will ever touch. The Allstar Performance Distribution Block with integrated Proportioning Valve (ALL48037) is the ultimate solution for enthusiasts who are tired of cluttered brake plumbing and inconsistent pedal feel. This all-in-one unit eliminates the need for separate tees and external valves by consolidating your master cylinder outlets, your front and rear brake lines, and your brake light switch into one compact, high-strength assembly. It is specifically designed to provide a clean, professional appearance while giving you the granular control necessary to dial in your brake bias for maximum stopping power without the fear of dangerous rear-wheel lock-up during hard deceleration.

What sets this distribution block apart is its precision-engineered manual proportioning valve. On many VW disc brake conversions, the rear brakes can become over-sensitive, leading to the rear end "coming around" on you in an emergency stop. By utilizing the adjustable knob on this block, you can fine-tune the fluid pressure sent to the rear calipers or wheel cylinders, ensuring your front brakes do the heavy lifting while the rears provide perfectly balanced stability. Furthermore, the built-in pressure-activated brake light switch simplifies your wiring harness significantly. It comes complete with a pigtail wiring harness and a protective rubber boot, ensuring that your electrical connections remain dry and corrosion-free even in the harshest environments. If you are serious about your air-cooled VW''s performance and safety, this is the hydraulic cornerstone your project deserves.

FITMENT

This distribution block is a universal performance upgrade and is highly recommended for the following air-cooled applications when upgrading to dual-circuit master cylinders or disc brake conversions:

• VW Beetle & Super Beetle: 1950 through 1979 (All models)
• VW Karmann Ghia: 1956 through 1974
• VW Bus / Type 2: 1950 through 1979 (Split Window and Bay Window)
• VW Type 3: 1961 through 1973 (Squareback, Fastback, Notchback)
• VW Thing / Type 181: 1973 through 1975
• Custom Rail & Dune Buggy: All years and chassis styles (Manx, Berrien, Chenowth)
• Baja Bugs: Ideal for high-travel suspension setups requiring custom line routing

SPECS

• Manufacturer: Allstar Performance
• Part Number: ALL48037
• Port Thread Size: 3/8 In-24 (Standard for most 3/16 In brake lines)
• Fitting Style: Accepts 3/16 In Inverted Flare fittings
• Valve Type: Manual Adjustable Proportioning Valve
• Switch Type: Integrated Pressure-Activated Brake Light Switch
• Material: High-Grade Lightweight Aluminum Block
• Finish: Durable Black Anodized Coating for Corrosion Resistance
• Included Hardware: Mounting block, Proportioning valve, Brake light switch, Wiring pigtail, Rubber protective boot, and basic fittings
• Adjustment Range: Reduces pressure by up to 57% to the rear circuit

PRO TIPS

1. Mastering the Bias Adjustment

Setting your brake bias isn''t a "set it and forget it" task if you want the best performance. We recommend starting with the valve in the fully open position (turned all the way counter-clockwise). Take your VW to a safe, empty parking lot and perform several controlled stops from 30 MPH. If the rear wheels lock up before the fronts, turn the knob clockwise one full turn at a time until the front wheels lock slightly before the rears. This ensures that your car tracks straight during a panic stop and prevents the rear end from sliding out. Remember, as you add passengers or heavy gear to your roof rack, your weight distribution changes, and you may want to slightly readjust your bias for those specific trips.

2. Proper Line Flaring and Sealing

Since this block uses 3/8-24 threads for 3/16-inch inverted flare lines, it is absolutely vital that you use a high-quality double-flaring tool when making your custom lines. Many "soft" lines found in cheap kits can leak under the high pressures generated by a performance master cylinder. When installing your fittings into the Allstar block, do not use Teflon tape or liquid thread sealant on the threads. The seal is created by the flare of the tube against the seat inside the block, not the threads themselves. Using sealant can actually migrate into the proportioning valve and cause a mechanical failure or a blockage in your brake system.

3. Bleeding the Integrated System

When bleeding your brakes with this distribution block installed, always start with the wheel furthest from the master cylinder (usually the passenger rear) and work your way closer. Because this block contains an adjustable proportioning valve, you should have the valve turned to the "full pressure" or fully open position during the bleeding process. This ensures there is no restriction in the internal galleries, allowing air bubbles to move freely out of the lines. Once you have a firm pedal and have verified there are no leaks at the pigtail switch or the adjustment knob, then you can begin the process of dialing in your rear pressure bias.