Autometer 5 Sport-Comp In Das

OVERVIEW

When you are pushing a high-performance air-cooled engine to its absolute limits, precision isn''t just a luxuryit''s a necessity. The AutoMeter 5-inch Sport-Comp In-Dash Tachometer (ATM3990) is the gold standard for Volkswagen enthusiasts who demand accuracy and style. Designed with a massive 5-inch face, this tachometer provides an unmistakable visual reference for your engine''s RPM, ensuring you never miss a shift or over-rev your expensive power plant. Whether you are staging at the drag strip in a narrowed-beam Beetle or navigating technical trails in a custom sand rail, the iconic silver bezel and high-contrast black face of the Sport-Comp series offer a timeless look that complements both vintage and modern interior builds. This isn''t just a gauge; it''s a piece of professional-grade equipment that has been proven in the most grueling racing environments around the globe.

Engineered for versatility and durability, the ATM3990 features AutoMeter''s legendary air-core movement, which provides lightning-fast response times and smooth needle movement even under heavy vibration. This is particularly crucial for air-cooled VWs, which are known for their unique harmonic frequencies and rugged operating conditions. The unit is designed to work seamlessly with 4, 6, or 8-cylinder engines, making it the perfect upgrade for everything from a standard 1600cc dual-port to a massive 2332cc stroker engine. The perimeter incandescent lighting ensures that you have clear visibility during night-time cruises or late-night sessions at the track, while the rugged construction guarantees that it will withstand the dust of the desert and the heat of the engine bay. When you choose AutoMeter, you are investing in a legacy of performance that has dominated the automotive aftermarket for decades.

FITMENT

This tachometer is a universal high-performance component, but it is specifically favored for the following Volkswagen and off-road applications:

• Volkswagen Beetle (All Years): Ideal for custom dash panels or replacing the stock speedometer unit in race-prepped Type 1s.
• Volkswagen Karmann Ghia: Fits beautifully in custom three-gauge dash layouts for a pro-touring look.
• Volkswagen Bus (Type 2): A must-have for Bus owners running larger displacement engines that require careful RPM monitoring.
• Volkswagen Type 3 (Squareback, Fastback, Notchback): Perfect for high-performance street builds.
• Volkswagen Thing (Type 181): Rugged enough for the open-air environment of a Thing.
• Dune Buggies & Sand Rails: The 5-inch face is easy to read while bouncing through the dunes in a Meyers Manx or long-travel rail.
• Custom Drag Cars: The 10,000 RPM range is essential for high-revving turbo or nitrous-fed air-cooled dragsters.

SPECS

• Brand: AutoMeter
• Series: Sport-Comp
• Part Number: 3990
• Face Diameter: 5 Inches (127mm)
• RPM Range: 0 - 10,000 RPM
• Gauge Type: In-Dash (Flush Mount)
• Movement: Air-Core (Precision dampened)
• Compatibility: 4, 6, and 8-cylinder engines
• Ignition Compatibility: Works with points, electronic ignitions, and most 12V high-performance racing ignitions (including MSD).
• Lighting: Perimeter Incandescent (Includes red and green bulb covers for custom color tinting).
• Bezel: Brushed Silver Aluminum
• Face Color: Black with White Numbers
• Pointer: High-Visibility Red

PRO TIPS

Tip 1: Ensure a Rock-Solid Ground

In the world of air-cooled Volkswagens, electrical gremlins are often traced back to poor grounding. When installing your AutoMeter tachometer, do not rely on the dash metal alone for your ground connection. We highly recommend running a dedicated ground wire from the gauge directly to the chassis or the negative terminal of the battery. This ensures the needle remains steady and prevents "jumpy" readings that can occur when the ignition system interferes with a weak ground circuit. Double-check all connections with a multimeter to ensure you have zero resistance for the most accurate RPM data possible.

Tip 2: Use a Tach Adapter for Modern Ignitions

If you have upgraded your VW to a high-output capacitive discharge ignition (CDI) system like an MSD 6AL or a Pertronix Digital HP, the standard coil signal may not be compatible with the tachometer''s input. In these cases, you should use the "Tach Output" port on the ignition box rather than the negative side of the coil. If your specific ignition setup still produces a "noisy" signal or no signal at all, installing an AutoMeter Tach Adapter (Part #9117) will clean up the pulse and ensure your Sport-Comp gauge reads perfectly across the entire 10,000 RPM sweep.

Tip 3: Custom Dash Clearance and Mounting

The 5-inch Sport-Comp is a large-format gauge, which is what makes it so easy to read at a glance. However, when mounting this in a stock VW Beetle dash, you will likely need to perform some clearancing or use a custom fiberglass or aluminum dash panel. Before you cut, always measure twice and check for obstruction behind the dash, such as wiper linkages or wiring harnesses. We recommend using a high-quality hole saw specifically rated for the material you are cutting to ensure a professional, snug fit. If you are mounting this in an off-road rail, consider using a rubber-isolated mounting bracket to further protect the internals from extreme jarring.