22mm Buggy Master Cylinder for 2 or 4 Wheel Brakes

OVERVIEW

Upgrade your stopping power and eliminate that spongy pedal feel with the EMPI Large Bore 22mm Buggy Master Cylinder. When you move beyond stock drum brakes and venture into the world of high-performance 2-wheel or 4-wheel disc brake conversions, your standard 17mm or 19mm master cylinder simply cannot move enough fluid volume to actuate larger calipers efficiently. This 22mm powerhouse is engineered specifically for the air-cooled enthusiast who demands a firm, responsive brake pedal in their dune buggy, sand rail, or custom street rod. By increasing the bore diameter, you effectively increase the volume of fluid displaced with every stroke, ensuring that your disc brake pistons have the pressure they need to clamp down hard when it matters most.

The beauty of this EMPI master cylinder lies in its "all-in-one" design, which is based on the rugged pre-1966 Type 2 Bus architecture. Unlike modern dual-circuit systems that require complex plumbing and remote-mounted fluid reservoirs, this unit features an integrated, thread-on brake fluid reservoir. This compact configuration is a lifesaver for buggy builders working with limited space or custom chassis where mounting a separate reservoir would be a fabrication nightmare. With four M10x1.0mm threaded ports, you have the ultimate flexibility to run front and rear lines, install multiple brake light switches, or plug unused ports to suit your specific plumbing layout. It''s the definitive solution for simplified, high-performance braking in the air-cooled world.

FITMENT

While this master cylinder is a universal favorite for custom builds, it is designed to fit the following applications and configurations:

• Dune Buggies: All years (Fiberglass bodies, Manx-style, and Tube Chassis).
• Sand Rails: All custom frames and off-road rails.
• VW Type 2 Bus: 1950 through 1966 (Direct fit replacement style).
• Custom VW Trikes: Ideal for 3-wheel configurations requiring high fluid volume.
• VW Beetle/Type 1: Can be used in custom "race-only" or "off-road" single-circuit conversions (may require pedal assembly modifications).
• Brake Setups: Optimized for 4-Wheel Disc, 2-Wheel Disc/2-Wheel Drum, or heavy-duty 4-Wheel Drum configurations.

SPECS

Every component is manufactured to meet or exceed rigorous standards for off-road and street performance. Here are the technical details:

• Bore Diameter: 22.2mm (Large Bore) for maximum fluid displacement.
• Material: Heavy-duty cast iron housing with a natural finish.
• Reservoir Type: Thread-on high-density plastic reservoir (Included).
• Port Thread Size: M10 x 1.0mm (Standard VW brake line threading).
• Total Ports: 4 threaded ports for lines and switches.
• Circuit Style: Single Circuit (Single Stage) design.
• Part Number: EMPI 00-6112-0.
• Weight: Approximately 1.89 lbs.

PRO TIPS

1. The Golden Rule of Bench Bleeding

Never install a master cylinder directly onto the vehicle without bench bleeding it first. Because this is a single-circuit unit with an integrated reservoir, air can easily get trapped in the piston bore. Before mounting, secure the cylinder in a vice, fill the reservoir with fresh DOT 3 or DOT 4 fluid, and use a screwdriver or pushrod to manually stroke the piston until no air bubbles emerge from the ports. This ensures that you aren''t fighting trapped air for hours during the final bleeding process at the wheel cylinders or calipers.

2. Managing the Four-Port Layout

Since this master cylinder features four ports, you have several options for plumbing. Most builders use two ports for the brake lines (one to the front "T" and one to the rear "T") and the remaining two ports for hydraulic brake light switches. If your wiring harness only uses one switch, or if you are using a mechanical switch at the pedal, you must use M10x1.0mm threaded plugs with copper crush washers to seal the unused ports. Always double-check for leaks at these plugs after the system is pressurized, as they are a common source of "mystery" fluid loss.

3. Pushrod Clearance and Free Play

When installing this on a custom buggy or sand rail, pay extremely close attention to the pushrod length. There must be approximately 1mm of "free play" between the pedal pushrod and the master cylinder piston when the pedal is at rest. If the pushrod is too long and keeps constant pressure on the piston, the compensating port inside the cylinder will remain closed. This prevents fluid from returning to the reservoir, causing your brakes to "drag" and eventually lock up completely as the fluid heats up and expands. Always verify that the piston returns fully to its seat after every pedal stroke.