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Old 05-31-2018, 11:47 AM   #1
G-NUT
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stock compression ratio on a 1985 C20 350?

Anyone know what the compression ratio is on bone stock 350 from a 1985 C20? Flat top or dished pistons?

Thanks
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Old 06-01-2018, 05:31 PM   #2
Alex V.
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Re: stock compression ratio on a 1985 C20 350?

Looks like 8.2 or 8.3.
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Old 06-01-2018, 05:33 PM   #3
G-NUT
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Re: stock compression ratio on a 1985 C20 350?

I have the LT9. So it looks like it's 8.3:1

Thank you very much for that.
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Old 06-03-2018, 07:33 AM   #4
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Re: stock compression ratio on a 1985 C20 350?

Can you shed some light on why you needed this information ? Just curious.
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Old 06-03-2018, 06:22 PM   #5
G-NUT
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Re: stock compression ratio on a 1985 C20 350?

I'm looking to add a "RV" cam, mild cam and heads. I'd like to keep my comp ratio to about 9.1 to 9.5. Looking at World Products 170cc runner, 67cc heads with 0.039 squish Felpro gaskets.
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