Valve Guide Undersized Inside Diameter
All IE valve guides are sold with an undersized inside diameter. This allows the engine builder to ream the guides after installation and set the stem-to-guide clearances exactly where they need to be since different valve materials require different clearances. This feature eliminates any guesswork associated with replacing the guides. To make installation simple, we machine a small centering lip on the tip of each valve guide, which allows them to press into the head straight and consistently. See below section for recommended valve guide clearances.

Recommended Clearances
Every engine builder will have his or her own specs, but as a general rule of thumb, we use the following valve-to-guide clearances.

• Ferra Stainless Intake - 0.0008" to 0.0012"
• Ferra Super Alloy Exhaust - 0.0013" to 0.0015"
• Ferra Stainless Exhaust - 0.001" to 0.0015"
• Supertech Stainless Intake - 0.0014" to 0.0024"
• Supertech Stainless or Inconel Exhaust - 0.0018" to 0.0028"

Technical Information

Valve Guide Mechanics
Valve guides are small cylindrical bushings that press into a cylinder head, giving valves a place to reciprocate with minimal friction and wear. They facilitate valve movement and keep them perfectly centered on the valve seats. Lastly, they allow heat to transfer from the combustion chamber into the cylinder head, which is then cooled by engine coolant.

Why You Should Replace Your Valve Guides
When it comes time to rebuild your cylinder head, it's very likely that you will find the OEM valve guides worn beyond wear limits. As mileage begins to add up, the inside diameter of your valve guides will wear, causing excessive clearance with the valve stems. Even on engines that have no modifications, it is common to see oil consumption, irregular valve wear, or even complete valve failure if the guides have become excessively worn.

Performance Upgraded Valve Guides
Integrated Engineering performance valve guides work as direct OEM replacements while offering several unique features to improve performance and increase longevity. IE valve guides are manufactured in our CNC machine shop from a proprietary bronze alloy and feature ultra-high concentricity for exact valve placement. This ensures that the head of the valve sits in the exact center of the seat, removing any possibility of leaks. Our premium alloy improves wear resistance, reduces friction, and improves heat transfer. By increasing thermal conductivity by 10%, you can expect extended valve life and reduced wear on valvetrain components.

Aerodynamic Design
To increase airflow through the intake and exhaust ports, we have designed our valve guides with an aerodynamic tip that does not protrude into the airstream like the factory units. IE valve guides are designed to directly replace the factory guides and work well for all rebuilds, whether it be an OEM refresh or a complete race engine build!