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Depends on CC's, from what I have measured from different cylinders over the years:

310 Race gas 28CC
310 Pump Gas 29CC
330 Race Gas 31CC
330 Pump Gas 32CC
350 Race Gas 33-34CC
350 Pump Gas 35-36CC

Carlos
 

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The 370 cylinder I have has an 81mm bore. The dome volume couldn't possibly be the same as a 350 cylinder.
 

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The 370 cylinder I have has an 81mm bore. The dome volume couldn't possibly be the same as a 350 cylinder.
Actually it is, and in some 370's it is a smaller CC volume than a standard 350CC. For Example; the New ESR 370 CEO with 81MM piston has a much smaller Dome volume than a standard 350-370CC since the Piston is Concave and not Convex.

The required Dome CC is a function of not just bore size, it is directly related to the Piston Top face shape. A standard 81MM (370CC Cylinder) piston has less (closer to Flat) of a Convex curve than a 78MM (350CC Cylinder) whose top face shape is a lot more Convex...therefore; while the Dome CC's may be the same between a 350Cc & 370CC Cylinder, the total Head Volume is greater on the 370CC than the 350CC....

Never say "couldn't possibly be the same"...:)

Carlos
 
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