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Am I missing something here?
Bore 4.280
Stroke 4.000
Means cylinder volume would be 57.54894 ci
If I wanted 10:1 compression I would divide 57.54894 by 10 = 5.754894
Total chamber volume should equal 5.754894 ci or metric 94.30581 cc
If deck clearance is .020", clearance area volume is .2877446 ci or 4.7153cc
If gasket thickness is .035, gasket area volume is .5035531 ci or 8.2518 cc

The volume of 118cc heads converted to inches equals 7.2008. So here goes

Gasket = .5035531ci
Deck Clearance = .2877446 ci
Head volume = 7.2008017ci
This equals 7.9920994ci, convert that and you've got 130.9670449cc
If I subtract 94.30581 from 130.9670449 I get 36.6612349
So is this the correct way of doing this? would a 37cc dome put me at 10:1?
 

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Right... its total volume (swept AND chamber) divided by chamber volume. Not displacement divided by chamber.

If you have a displacement in one cylinder of 1000cc and a 100cc chamber, your compression is not 10:1. Total volume is 1100cc divided by 100 cc chamber for 11:1 compression.
 
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