No, the chamfer is just really huge and kills a lot of compression off. It almost defeats the purpose of the flat top.
Ah, so it would be more than the 4cc for the valve reliefs. It's possible that the photo is not the actual 307 piston and may not have the chamfer.
I haven't had my head off yet to do some measurements on the factory head gasket, deck clearance or piston cc. When I play around with the compression calculator to try and achieve 8.1:1 SCR I assume 76cc chambers, .015" x3.875" gasket, .005" deck clearance and that comes up with a 16cc dished piston. Is that about right for the stock piston?
