L92 heads milled?
At .006 per cc if they were 72 cc to begin with you should be pretty darn close. Most accurate way is to pour them but .006 per cc is the accepted math. Problem is they say +/- 2cc for the cc rating from the factory 
Casting Number 12595364 or 12582716
Valve Angle 15-degree
Combustion Chamber 70cc*
Intake Port Volume 279cc*
Exhaust port Volume 99cc*
Minimum Cylinder Bore 4.000”
* Approximate, Numbers are within +/- 2cc’s
Milling Information for Combustion Chamber Sizing
- Approximately 0.006” per 1-cc
For 68-cc Chamber Remove 0.012”
For 65-cc Chamber Remove 0.030”
Casting Number 12595364 or 12582716
Valve Angle 15-degree
Combustion Chamber 70cc*
Intake Port Volume 279cc*
Exhaust port Volume 99cc*
Minimum Cylinder Bore 4.000”
* Approximate, Numbers are within +/- 2cc’s
Milling Information for Combustion Chamber Sizing
- Approximately 0.006” per 1-cc
For 68-cc Chamber Remove 0.012”
For 65-cc Chamber Remove 0.030”
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On The Tree
Joined: Mar 2009
Posts: 149
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At .006 per cc if they were 72 cc to begin with you should be pretty darn close. Most accurate way is to pour them but .006 per cc is the accepted math. Problem is they say +/- 2cc for the cc rating from the factory
Casting Number 12595364 or 12582716
Valve Angle 15-degree
Combustion Chamber 70cc*
Intake Port Volume 279cc*
Exhaust port Volume 99cc*
Minimum Cylinder Bore 4.000”
* Approximate, Numbers are within +/- 2cc’s
Milling Information for Combustion Chamber Sizing
- Approximately 0.006” per 1-cc
For 68-cc Chamber Remove 0.012”
For 65-cc Chamber Remove 0.030”
Casting Number 12595364 or 12582716
Valve Angle 15-degree
Combustion Chamber 70cc*
Intake Port Volume 279cc*
Exhaust port Volume 99cc*
Minimum Cylinder Bore 4.000”
* Approximate, Numbers are within +/- 2cc’s
Milling Information for Combustion Chamber Sizing
- Approximately 0.006” per 1-cc
For 68-cc Chamber Remove 0.012”
For 65-cc Chamber Remove 0.030”
so 40 is gonna be 63cc?
