GSC P-D Subaru EZ30 PHZ 1 Exhaust Valve Guide Stopper Style OVERSIZE +.003 - Single

This is a single GSC Power Division exhaust valve guide stopper, specifically designed for Subaru EZ30 PHZ 1 engines. It's an oversize part, measuring +.003 inches, intended to replace worn or damaged valve guides during an engine rebuild. Proper valve guide function is crucial for sealing, preventing oil from entering the combustion chamber, and ensuring the valve operates smoothly.

This stopper style guide is well-made and meant to be a direct replacement for the factory part, simplifying installation for mechanics. The +.003 oversize means it's designed to be honed to a precise fit within the cylinder head, accommodating heads where the original guide bore has been enlarged due to wear or previous machining. Using the correct oversize guide ensures a tight seal and proper valve alignment, which is essential for engine performance and longevity.