90.5mm + 92mm Copper Head Shim Kit (0.050" Thick)

Copper cylinder head shims designed for aircooled VW performance engines using 90.5mm or 92mm cylinders. These precision shims are used between the cylinder barrel and cylinder head to accurately adjust deck height and compression ratio while also improving sealing at the head to barrel surface.

Manufactured from copper for excellent heat transfer and sealing properties, these shims are commonly used in high performance, stroker and rebuilt engines where precise compression ratio setup is critical. Copper shims help reduce the risk of compression leaks between the cylinder and head, especially on engines running higher compression or increased temperatures.

By altering deck height, these shims allow engine builders to fine tune combustion chamber volume, helping achieve the correct compression ratio for street, performance or turbocharged applications. Ideal for engines where machining alone cannot achieve the required setup.

Specifications

• Material: Copper
• Thickness: 0.050″ (1.27mm)
• Barrel Size Compatibility: 90.5mm and 92mm
• Quantity: Set of 4 for 1 engine

Vehicle Fitment

Aircooled VW

Suitable for any aircooled VW Type 1 based engine fitted with:

• 90.5mm cylinders
• 92mm cylinders

Common applications include:

• VW Beetle performance engines
• VW Karmann Ghia performance engines
• VW Splitscreen Bus upgraded engines
• VW Baywindow Bus upgraded engines
• VW Type 3 performance engines
• VW Buggy and Baja engines
• Stroker and high compression Type 1 engines

What These Shims Do

• Adjust deck height
• Fine tune compression ratio
• Improve cylinder to head sealing
• Help prevent compression leaks
• Assist with accurate engine blueprinting

Additional Parts Recommended

• Cylinder base shims
• Copper head gaskets
• Performance cylinder head nuts
• Torque wrench for accurate assembly
• Deck height measuring tools
• Compression ratio calculation kit

Important Installation Notes

• Cylinder head and barrel surfaces must be perfectly clean and flat
• Compression ratio should always be checked before final assembly
• Correct torque settings must be followed
• Commonly used in performance and stroker engine builds