Shims for Billet Alternator Pulley, 5 Piece

OVERVIEW

When you upgrade to a high-performance billet alternator or generator pulley, you quickly realize that the standard factory clearances and tolerances no longer apply. These EMPI Shims for Billet Alternator Pulleys are an absolute necessity for any enthusiast running a custom machined pulley setup on their air-cooled Volkswagen. Unlike the stock stamped steel pulleys that utilize a specific factory shim diameter, billet pulleys are precision-engineered with different offsets and internal seat requirements. Using stock shims on a billet pulley can lead to improper seating, belt misalignment, or even catastrophic damage to the pulley faces. These shims are specifically designed to bridge that gap, ensuring that your fan belt has the perfect amount of tension. This is critical because your VW''s entire cooling system relies on that belt to spin the fan at the correct RPM; without the right shims, you risk overheating your engine or throwing a belt at high speeds.

This 5-piece set is specifically engineered to provide the incremental adjustments needed to dial in your belt tension with professional-grade precision. In the high-stakes world of air-cooled performance, "close enough" simply isn''t good enough when it comes to your charging and cooling systems. Whether you are building a show-quality Beetle, a rugged sand rail, or a high-revving street Ghia, having a dedicated set of billet-compatible shims in your toolbox is a smart move for long-term reliability. These shims are manufactured from high-quality, heat-treated steel to resist compression and warping under the high-torque loads of a performance engine. By using these EMPI-specific shims, you are ensuring that your billet pulley performs exactly as intended, providing a secure, slip-free grip on the belt while maintaining the sleek, custom aesthetic that only billet aluminum can provide.

FITMENT

These shims are designed for use with EMPI and most aftermarket billet aluminum alternator or generator pulleys. They are compatible with the following models using a billet pulley upgrade:

• Volkswagen Beetle: 1950 through 1979 (All Type 1 Engines)
• Volkswagen Karmann Ghia: 1956 through 1974
• Volkswagen Bus / Transporter: 1950 through 1971 (Type 1 Engine configurations)
• Volkswagen Type 3: 1962 through 1973 (Squareback, Fastback, Notchback)
• Volkswagen Thing: 1973 through 1974
• Custom Applications: Dune Buggies, Sand Rails, Trikes, and Baja Bugs utilizing a VW Type 1 upright engine with a billet pulley.

SPECS

• Quantity: 5 Pieces per package.
• Material: High-tensile strength stamped steel.
• Compatibility: Specifically for Billet Alternator and Generator Pulleys (Not for stock steel pulleys).
• Application: Belt tension adjustment and spacing.
• Part Number: 16-9709-0.
• Finish: Natural steel.
• Inner Diameter: Optimized for standard VW alternator/generator shafts.

PRO TIPS

The Outside Storage Secret

One of the most common mistakes builders make is losing the extra shims they don''t use for tensioning. Always remember that all 5 shims (plus any others you may have) must remain on the pulley assembly at all times. If you only need 2 shims between the pulley halves to get the correct belt tension, the remaining 3 shims should be placed on the outside of the outer pulley half, right under the nut and lock washer. This ensures that the pulley nut tightens down against a solid stack and that you always have your adjustment shims available if the belt stretches over time.

The Half-Inch Deflection Rule

To ensure your cooling fan is spinning efficiently without putting excessive strain on your alternator or generator bearings, you must check the deflection of the belt after installing your shims. With the engine off, press down firmly on the belt midway between the top and bottom pulleys. You should see approximately 1/2 inch (12mm) of deflection. If the belt is tighter than this, you need to add more shims between the pulley halves to spread them apart. If it is looser, you must remove shims from between the halves to bring them closer together, forcing the belt higher in the groove.

Inspect for Burrs and Debris

Before installing these shims on your high-dollar billet pulley, take a moment to inspect the mating surfaces of the pulley itself and the shims. Because billet aluminum is softer than the steel shims, any tiny burr or piece of grit trapped between the shim and the pulley can "mar" the surface and lead to a pulley that wobbles. I recommend a very light coat of anti-seize on the shaft itself, but keep the shim faces clean and dry. Tighten the pulley nut to the factory torque spec (usually around 43 ft-lbs), and then rotate the engine by hand to ensure the belt seats properly before you fire up the engine.