Part Number for O-200 Piston Rings

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edidin
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Part Number for O-200 Piston Rings

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For a C-85 stroker; understanding is that it has C-85 cylinders but O-200 pistons. Thus if changing a cylinder would want to have O-200 ring set available.
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6643
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Re: Part Number for O-200 Piston Rings

Post by 6643 »

Yes. The rings need to fit the piston. You also need to consider the type of bore. Chrome cylinders require iron rings whereas steel cylinders use chrome rings. Chrome rings will seize in chrome cylinders.
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edidin
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Re: Part Number for O-200 Piston Rings

Post by edidin »

Non-chromed cylinders.
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6643
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Re: Part Number for O-200 Piston Rings

Post by 6643 »

edidin wrote: ↑Wed Sep 08, 2021 10:51 am Non-chromed cylinders.
So, you want the "standard" set with the chrome top ring. I believe that is 638109A1. If your bore is oversize, add e.g. "P005" for .005 over.

Turns out both pistons use the same ring set. Chalk it up to old timer's disease.
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