9mm Exhaust Valve Guide - Type 4 Engines

This 9mm exhaust valve guide is designed for use across a wide range of Volkswagen Type 4 engines, including 1700cc, 1800cc, and 2000cc air-cooled units fitted to Baywindow Buses, as well as Type 25 (T3) Buses in both air-cooled and water-cooled configurations. It is also suitable for Porsche 914 Type 4 engines and certain Type 1 1600cc engines that use 9mm stem exhaust valves.

The valve guide plays a critical role in engine operation by accurately locating the exhaust valve within the cylinder head. It ensures the valve moves smoothly in a straight line, maintains correct valve seating, and transfers heat from the exhaust valve into the cylinder head for effective cooling. A worn guide can lead to excessive oil consumption, poor compression, valve burning, and reduced engine efficiency, making replacement essential during engine rebuilds or cylinder head overhauls.

Manufactured to precise tolerances, this guide provides a secure interference fit within the cylinder head, ensuring long-term stability even under high exhaust temperatures. Depending on supplier availability, some guides may be supplied without the original top shoulder. This does not affect functionality, as the guide is correctly retained by its press fit once installed and performs identically in service.

Each engine requires 4 exhaust valve guides, and these are sold individually, allowing you to purchase exactly the quantity needed for your rebuild.

Vehicle & Engine Fitment:

• T2 Baywindow Bus – 1700cc, 1800cc, 2000cc Type 4 (1972–1979)

• T25 / T3 Bus – Type 4 air-cooled and water-cooled engines (1980–1992)

• Porsche 914 – Type 4 engines (1970–1976)

• VW Type 1 – Selected 1600cc engines with 9mm stem exhaust valves

Key Features:

• 9mm exhaust valve stem compatibility

• Precision-machined for accurate valve control

• Excellent heat transfer for exhaust valve cooling

• Durable construction for long service life

• Shoulderless versions may be supplied (no impact on performance)

Recommended Associated Parts:

• 9mm exhaust valves

• Valve guide seals (where applicable)

• Valve seats (recommended during head reconditioning)

• Valve springs, retainers, and collets if rebuilding cylinder heads