Rocker Arm Shim Set, .010 Thick, 19.5mm, Set of 8

Precision Valve Train Alignment for Peak Performance

When you are building a high-performance air-cooled Volkswagen engine, the difference between a reliable powerhouse and a ticking time bomb often comes down to the smallest measurements. The EMPI Rocker Arm Shim Set is an essential component for any engine builder who understands that "close enough" is never good enough for the valve train. These .010-inch thick shims are designed to provide the ultimate precision when setting up your rocker arm geometry and side play. By utilizing these shims, you can ensure that your rocker arms are perfectly centered over the valve stems, which minimizes side-loading on the valve guides and prevents premature wear of the valve tips. Whether you are running a stock 1600cc daily driver or a high-revving 2332cc stroker, achieving the correct lateral spacing on your rocker shafts is critical for maintaining a quiet, efficient, and long-lasting top end.

This set of eight precision-stamped shims is specifically engineered for use with high-performance bolt-on rocker shafts or any assembly where the factory wavy washers have been discarded in favor of a solid spacer setup. In the world of VW performance, the standard spring-loaded wavy washers often allow for too much lateral movement under high RPM loads, leading to inconsistent valve lift and unwanted noise. By transitioning to a solid spacer and shim arrangement, you lock in your settings for consistent performance across the entire powerband. These 19.5mm internal diameter shims fit snugly over standard and heavy-duty rocker shafts, providing a stable foundation that resists the harmonic vibrations common in high-lift cam applications. Don''t let a sloppy valve train rob you of horsepower or destroy your cylinder heads; invest in the precision that EMPI provides with this specialized shim kit.

Comprehensive Fitment for Air-Cooled VW Engines

These rocker arm shims are designed for universal application across the most popular Volkswagen air-cooled engine configurations. They are compatible with:

• Volkswagen Beetle: All years and models equipped with Type 1 upright engines (1200cc, 1300cc, 1500cc, and 1600cc).
• Volkswagen Karmann Ghia: All years utilizing Type 1 engine platforms.
• Volkswagen Bus / Type 2: 1950 through 1971 (Single-port and Dual-port configurations).
• Volkswagen Type 3: Squareback, Fastback, and Notchback models.
• Volkswagen Thing (Type 181): All models.
• Dune Buggies and Sand Rails: Any custom build utilizing a VW Type 1 based case and rocker assembly.

Technical Specifications and Dimensions

Built to exacting standards, these shims provide the consistency required for professional-grade engine assembly. The technical specifications include:

• Thickness: .010 inch (0.254mm) for fine-tuning side play.
• Internal Diameter (ID): 19.5mm (Optimized for standard and performance rocker shafts).
• Material: High-tensile precision-stamped steel for maximum durability and resistance to compression.
• Quantity: Set of 8 pieces (Enough for a complete engine build).
• Manufacturer: EMPI.
• Part Number: 21-2168-0.
• Application: Designed for use with solid rocker shaft kits and high-performance rockers (1.1:1, 1.25:1, and 1.4:1 ratios).

Master Specialist Pro Tips for Installation

Tip 1: Target the Perfect Side Play

When you are setting up your solid rocker shafts, your goal is to achieve a side play of between .004" and .006". Use a high-quality feeler gauge to check the gap between the rocker arm and the shaft support or the adjacent spacer. If the rocker is too tight, it will bind as the engine reaches operating temperature and the metals expand, potentially leading to a dropped valve. If it is too loose, you will experience excessive "valve clatter" and the rocker tip will skip across the valve stem. These .010" shims are the perfect "middle-ground" size to help you dial in that perfect tolerance when standard .015" or .020" shims are just a bit too thick.

Tip 2: Check for Burrs Before Installation

Even though these are precision-stamped, it is always a best practice for a master builder to inspect each shim for tiny burrs or "flash" on the edges. When you stack multiple shims together, a single tiny burr can throw off your total measurement by several thousandths of an inch. I recommend lightly dragging the shim across a piece of 600-grit wet/dry sandpaper on a flat glass surface or a machinist''s plate before installation. This ensures that your stack is perfectly flat and your measurements are 100% accurate. Remember, the key to a quiet VW engine is the elimination of these tiny inconsistencies.

Tip 3: Lubrication and Centering

Never install your rocker arm shims dry. During the initial startup, before the oil pressure has fully reached the top of the heads, these shims can experience friction heat. Apply a small amount of high-pressure assembly lube to both sides of each shim as you slide them onto the shaft. Additionally, always prioritize centering the rocker arm tip over the valve stem first, then use the shims to fill the remaining gaps. If you have to choose between perfect side play and perfect centering, prioritize centering the rocker on the valve stem to ensure the longevity of your valve guides and to prevent the rocker from "walking" off the edge of the valve tip at high RPMs.