Performance Cylinder Head, 85.5mm Bore, with Single Springs

Performance Cylinder Head - 85.5mm Bore with Single Valve Springs

Restore your engine's power and efficiency with this Performance Cylinder Head from Appletree Auto. Designed specifically for 1600cc air-cooled Volkswagen engines, this head features a standard 85.5mm bore and comes fully assembled with performance-grade single valve springs. Each head is equipped with 35.5mm intake and 32mm exhaust valves, precision-seated to ensure maximum compression and flow. Whether you are replacing a cracked factory head or building a fresh 1600cc long block, these heads provide the reliability and cooling capacity needed for a dependable daily driver or weekend cruiser.

These performance heads are cast from high-quality aluminum alloy to provide superior heat dissipation, helping your air-cooled engine run cooler under load. They are designed to accept standard 12mm "long reach" spark plugs and feature clean, well-defined cooling fins for optimum thermal management. Appletree Auto ensures these heads meet strict tolerances, making them a direct-fit replacement for your original Type 1 engine components. Sold individually, these heads are the perfect foundation for a top-end refresh on any classic VW project.

Product Fitment & Compatibility

This cylinder head is designed for 1600cc Air-Cooled Type 1 engines with a standard 85.5mm piston and cylinder bore. It is compatible with both single-port and dual-port configurations depending on your intake manifold setup.

• Volkswagen Beetle: 1966 - 1977 (1600cc Engines)
• Volkswagen Super Beetle: 1971 - 1979
• Volkswagen Karmann Ghia: 1966 - 1974 (1600cc Engines)
• Volkswagen Bus / Transporter (Type 2): 1963 - 1971 (1600cc Engines)
• Volkswagen Thing (Type 181): 1973 - 1974
• Custom Sand Rails & Dune Buggies: All years (1600cc Type 1 based engines)

Tech Tips & Installation Advice

• Torque in Sequence: When installing new heads, always use a calibrated torque wrench and follow the factory tightening sequence. Tighten the head nuts in three stages (typically 7, 14, and finally 18-23 ft-lbs) to ensure the head seats evenly against the cylinders and prevents compression leaks.
• Spark Plug Selection: These heads are designed for 12mm threads. Always use a small amount of anti-seize on the spark plug threads to prevent the plugs from galling or seizing in the aluminum head over time. Hand-thread the plugs first to avoid cross-threading. NGK D7EA, D8EA, D9EA, or DP8EA9
• Check Valve Lash: After installing the heads and rocker shafts, you must set your valve lash (clearance). For most stock or mild performance cams, we recommend .006" for both intake and exhaust valves while the engine is cold. Re-check the lash after the first 500 miles of operation.
• Pushrod Geometry: If you are using an aftermarket high-lift camshaft, verify your pushrod length and rocker arm geometry. Improper geometry can lead to premature valve guide wear or even valve spring "coil bind," which can cause catastrophic engine failure.
• Clean Cooling Fins: Before final assembly, ensure the cooling fins are free of any casting flash or shipping debris. Maximum airflow between the fins is critical for the longevity of aluminum cylinder heads in air-cooled applications.