Engines and Components› Cylinder Heads and Components
COMP Cams
11/32in Valve Stem Seals Posi. Stop Teflon .530
SKU: C007 503-16
Moderate — 2–4 hours
Description
Part #: 503-16
Fits: 11/32" Valve Stems / .530" Guides (.630" Seal Diameter). Valves Seals keep unwanted oil from entering the combustion chamber through clearance in the valve guides. Smaller diameter than COMP Umbrella Seals to allow use with double springs.
COMP's Positive Stop PTFE valve seals offer more clearance for dual springs with better sealing than o-ring or umbrella seals. These 503 seals have a .630" outer diameter and fit applications with 11/32" valves and .530" OD valve guides.
This product may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.
MIA's Description
Installation requires machining the top of the valve guide with a specialized 0.530-inch diameter cutter to ensure a proper fit. The seals feature a 0.630-inch seal diameter and are specifically sized to allow for the use of double valve springs.
Fitment
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Specifications
| Brand | COMP Cams |
| Part Number | C007 503-16 |
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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