2-5/8 Pro-Comp Liquid

OVERVIEW

When you''re pushing a high-performance air-cooled engine to its limits, whether it''s a high-revving 2275cc drag motor or a turbocharged sand rail screaming across the dunes, standard instrumentation simply won''t cut it. The AutoMeter 2-5/8 Pro-Comp Liquid-Filled Oil Pressure Gauge (ATM5423) is engineered specifically for the most punishing environments known to the Volkswagen world. Unlike standard dry gauges that suffer from needle bounce and internal wear due to the harmonic vibrations inherent in the flat-four boxer engine design, this Pro-Comp series gauge utilizes a specialized liquid filling to dampen the movement. This ensures a rock-steady needle reading even when you''re bouncing off the rev limiter or navigating a washboard trail in your Baja Bug. The 0-100 PSI range is perfectly calibrated for the high-pressure oiling systems used in performance VW builds, providing the critical data you need to protect your expensive investment from catastrophic bearing failure.

The Pro-Comp series has long been the gold standard for serious racers, and the 2-5/8 inch diameter face provides significantly better visibility than the smaller 2-1/16 inch alternatives often found in street cars. The striking silver bezel and high-contrast black face with crisp white numerals offer a professional, competition-ready aesthetic that looks right at home in a custom aluminum dash or a classic VDO-style layout. Because this is a mechanical gauge, it provides a direct, real-time physical link to your oiling system, eliminating the lag and potential electrical interference associated with electronic sending units. At Appletree Automotive, we understand that "good enough" isn''t in your vocabulary when it comes to engine vitals. This AutoMeter gauge represents the pinnacle of reliability, housing precision bronze Bourdon tube gear movements that are built to outlast the vehicle they are installed in. When every PSI counts, trust the brand that has dominated the drag strips and off-road circuits for decades.

FITMENT

While this is a universal high-performance gauge, it is the preferred choice for the following air-cooled and water-cooled Volkswagen applications and custom builds:

• VW Beetle (Standard & Super): 1946 through 1979 (Custom dash or pod mounting required).
• VW Bus / Type 2 (Split Screen & Bay Window): 1950 through 1979.
• VW Karmann Ghia: 1956 through 1974.
• VW Type 3 (Squareback, Fastback, Notchback): 1961 through 1973.
• VW Thing (Type 181): 1973 through 1974.
• Dune Buggies & Sand Rails: All custom tube chassis and fiberglass body applications (Manx, Berrien, etc.).
• Volkswagen-Based Trikes: All custom configurations.
• Off-Road Racing: Class 11, Class 5-1600, and unlimited desert racers.

SPECS

• Product Line: AutoMeter Pro-Comp Series.
• Gauge Type: Mechanical Oil Pressure.
• Gauge Size: 2-5/8 Inches (66.7mm) Diameter.
• Pressure Range: 0 to 100 PSI.
• Fill Type: Liquid-Filled (Glycerin) for vibration dampening.
• Face Color: Black with High-Contrast White Markings.
• Bezel Finish: Brushed Silver / Aluminum.
• Pointer Color: Fluorescent Red.
• Movement: Bronze Bourdon Tube Gear Drive.
• Fitting Size: 1/8 Inch NPT Male Thread on the back of the gauge.
• Illumination: Incandescent bulb and socket assembly included.
• Mounting Hardware: Includes mounting bracket and nuts.
• Tubing: Requires 1/8 inch nylon or copper pressure line (sold separately).

PRO TIPS

1. Use Copper Over Nylon for Maximum Safety

While many mechanical gauge kits come with nylon tubing, we strongly recommend upgrading to a copper line kit for your air-cooled VW. The engine compartment of a Volkswagen can reach extremely high temperatures, especially near the cylinder heads and exhaust. Nylon lines can become brittle over time or melt if they accidentally come into contact with a hot surface, leading to a massive oil leak inside your cabin. Copper lines offer much higher heat resistance and durability, ensuring that the 80+ PSI of hot oil stays contained within the line. Always use a rubber grommet when passing the line through the firewall to prevent the metal edges from vibrating through the tubing.

2. Don''t Forget the Pressure Equalization

Because this is a liquid-filled gauge, it is sensitive to internal pressure changes caused by temperature fluctuations. You will notice a small rubber plug on the top of the gauge casing. For the most accurate readings, especially if you experience significant altitude or temperature changes, you may need to "vent" the gauge. Simply use a pair of side-cutters to snip the tiny nipple off the top of the rubber plug after installation, or briefly pry the edge of the plug up to allow the internal pressure to equalize with the atmosphere. This prevents the "zero shift" that can sometimes occur with sealed liquid gauges, ensuring your 10 PSI at idle is actually 10 PSI.

3. Use a T-Adapter for Dual Protection

When installing this gauge on a VW Type 1, 2, or 3 engine, don''t simply remove your factory oil pressure "idiot light" sender. Instead, use a 1/8 inch NPT "T" or "Y" adapter at the engine block. This allows you to retain the factory pressure switch (which triggers the red dash light) while also feeding the AutoMeter mechanical gauge. The dash light provides an instant visual warning if pressure drops to zero while you''re focused on the road, while the AutoMeter gauge provides the granular data needed to monitor engine health and oil pump performance. It''s the ultimate double-safety setup for any serious air-cooled enthusiast.