Our special made Manganese Bronz Alloy valve guides are designed for full race or street performance use.  They are suitable for both intake and exhaust.

The aerodynamic nose of these guides are positioned at minimum protrusion into the port for optimum flow.

• Same Guide INT & EXH
• For intake side these guides are 4mm shorter than stock to reduce exposed length in port and improve flow.
• For exhaust side these are only 1mm shorter than the stock cast iron guides. We maintain this length to reduce wear with the softer manganese bronze material.

We do not recommend chopping the guides flush with the port contour.  This practice does not leave enough total guide length to stabilize the lateral thrust of the valve stem.  The precision movement of the valve off the seat is far more important than the small amount of flow increase gained.