i'm not trying to muddy the waters here, But...Plus, the 340/s piston has a raised pin height over the other pistons "like" it, allowing for an assumed longer rod that improves rod angle ratio for greater high RPM durability and power output from reduced piston skirt side loading, reduced frictional losses, reduced mean piston speed and increased piston TDC dwell time in the combustion cycle.
The 340S piston and the production piston are very similar. As far as I can tell, the pin location is the same. The rings are higher on the piston on the 340S, and the lower ring is indexed to the opposite side of the port.
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