The only thing I find questionable is the weight. Summit nor TFS list the weight of the piston. I'd give them a call and find out since they can be no lighter than an OEM piston per the rules. This should not be a problem since it is a .030 over piston but I could not verify.
A stock OEM piston weighs 565 gm. or more depending on the year made.
You're right, the piston I meant to list is TFS-51404000 (flat top) which puts the compression at aprox 10.0:1 so I will investigate the piston weight and possibly a thicker head gasket to lower the compression.
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