5 Pro-Comp Tach 900

OVERVIEW

When you are pushing a high-performance air-cooled Volkswagen engine to its absolute limits, you cannot afford to rely on a stock speedometer or a cheap, bouncy needle. The AutoMeter 5-inch Pro-Comp Tachometer (ATM6851) is the gold standard for serious VW racers and performance enthusiasts who demand precision and reliability. Featuring a massive 5-inch face for unparalleled visibility, this tachometer allows you to monitor your RPMs with surgical accuracy, whether you are staging at the drag strip or screaming through the dunes in a sand rail. The Pro-Comp series is legendary in the racing world for its rugged construction and resistance to the high-frequency vibrations often found in high-revving 2110cc or 2332cc stroker motors. With a 9,000 RPM range, this gauge is perfectly suited for those high-lift cams and dual-carb setups that breathe better at the top end of the power band.

What truly sets the ATM6851 apart is the integrated two-stage shift light system. This feature is a game-changer for Volkswagen owners who want to maximize their acceleration and protect their investment. The two-stage system allows you to set a specific RPM for your first shift and a different RPM for subsequent shifts, which is essential for compensating for wheel spin or different gear ratios in a close-ratio transaxle. The traditional black face with high-contrast white numbering and a glowing red pointer ensures that you can read your engine status at a glance, even in the middle of a night run. Designed to withstand the rigors of competition, this tachometer isn''t just an instrument; it is a vital piece of performance hardware that bridges the gap between your engine''s potential and your driving execution.

FITMENT

• Volkswagen Beetle (All Years): Perfect for dash-top mounting or custom center consoles.
• Volkswagen Karmann Ghia: Fits beautifully in performance-oriented cockpit builds.
• Volkswagen Type 2 Bus / Transporter: Ideal for monitoring high-load cooling and RPMs on long hauls.
• Volkswagen Type 3 (Squareback, Fastback, Notchback): Great for modified street machines.
• Volkswagen Thing (Type 181): Rugged enough for open-air off-road environments.
• Sand Rails and Dune Buggies: The industry standard for tube-chassis performance vehicles.
• Meyers Manx and Kit Cars: Provides a professional racing aesthetic and functional accuracy.
• Engine Compatibility: Works with 4, 6, and 8-cylinder engines with standard points or electronic ignitions.

SPECS

• Product Series: Pro-Comp
• Face Color: Traditional Black
• Bezel Color: Silver / Brushed Aluminum
• Pointer Color: Fluorescent Red
• Gauge Diameter: 5 Inches (127mm)
• RPM Range: 0 - 9,000 RPM
• Shift Light: Integrated Two-Stage Shift Light (Included)
• Illumination Type: Perimeter Incandescent (Includes Red and Green Bulb Covers)
• Operating Voltage: 12 Volts
• Mounting Style: Pedestal Mount (Can be mounted on dash, steering column, or roll cage)
• Movement: Air-Core (Provides fast response and durability)

PRO TIPS

Tip 1: Proper Signal Sourcing. When installing this tachometer on a VW with a modern CDI ignition box like an MSD 6AL, do not connect the green signal wire to the negative side of the coil. Instead, use the dedicated "Tach Output" port on the ignition box. Connecting directly to the coil on a high-output ignition system can damage the internal circuitry of the tachometer or result in erratic needle movement. Always use a high-quality, shielded wire for the signal lead to prevent electromagnetic interference from your spark plug wires.

Tip 2: Optimizing the Two-Stage Shift Light. To get the most out of your Pro-Comp tach, set your first stage shift light about 200-300 RPM lower than your peak power shift point. This compensates for human reaction time during the rapid acceleration of first gear. For the second stage, set it exactly at your engine''s safe maximum RPM. This allows you to stay in the "power pocket" longer in higher gears where the RPM climb is slower, ensuring you never over-rev your valvetrain while chasing that extra tenth of a second.

Tip 3: Chassis Grounding and Vibration. Air-cooled Volkswagens are notorious for "dirty" electrical grounds and significant engine vibration. Ensure the black ground wire is connected directly to a clean, unpainted part of the chassis or a dedicated grounding block. Additionally, when using the pedestal mount on a thin fiberglass dash or a vibrating metal dash, consider using a small rubber isolation pad between the mount and the surface. This will further stabilize the needle and extend the life of the internal air-core movement during high-RPM runs.