# piston volume...

• posted on August 1, 2005, 9:51 pm
What is the volume in cc's of a '79 chevy truck piston....... I am needing to calculate the compression of a stock piston used with 64cc chambers. Also what is the compressed thickness of a stock head gasket.......
I'm great with HP motors but i have no clue what the factory pistons or head gaskets spec put at..........Thanx
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• posted on August 2, 2005, 12:15 am
The piston volume as far as the dome is concerned for compression ratios, is only an issue when it is dished or domed, both of these specs would have to be researched based on the specific year and engine model. The compressed gasket thickness again, you would need to know the type of gasket and research that also. If you know the compression ratio of the existing combination, you would need to know the cc's of the heads on there now, you can calculate the new ratio. With as little info as you posted I assume this is the root of your question?

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• posted on August 2, 2005, 11:30 am
I'm sorry.....i should have been more specific as to engine size (350) I was trying to determine what volume in cc's the stock piston displaces..... i know it is a dished piston, but what volume is unknown to me. Thanx anyway
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'79 Chevy K-10

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• posted on August 2, 2005, 3:51 am
if you have been give a combustion chamber's volume as 64cc's, then you need to find out the stroke of the piston (h) and the radius (r) of the piston (1/2 the diameter)
mutiply the value r by itself (r x r), times the result by (h), and times that figure by Pi (3.1416) = the volume of the piston's stroke...........but you probably know this already
Divide this number by 64 and you have the compression ratio (almost)
The problem being the shape of the piston's head, any notches, and the thickness of the gasket (the last two will reduce the ratio by a slight amount)

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• posted on August 2, 2005, 11:35 am
Thank you for the effort Ken....... all i need is the volume in cc's of a stock '79 chevy 350 truck piston and factory gasket thickness.
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"ken" < snipped-for-privacy@aol.com> wrote in message

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• posted on August 2, 2005, 12:11 pm
The ONLY way to find out is to cc one, just because the mfg quotes xx cc's don't believe it till you pour one. I've had pistons domes be off by 1 cc from what they were quoted as.