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Well, I managed to find some hard graphite round stock (for better power piston) and order today, it may be a few days before it shows up and I was eager to try a better piston. I turned up this Aluminum piston today and left it .0015 oversize and polished it to fit bore.
  I could tell right away when I fit it to engine the fit was better when I rolled engine over.
  It makes a bit more speed and a bit less vibration being lighter BUT the best discovery is it makes More power. I think the reason is china does not polish fit, a lathe cut will leave "record player" fine radial micro grooves, this can be less with a radius dressed on the tool bit but polishing levels the surface finish.
  I think a stock china piston as it Runs in wears the high spots off the micro grooves and we are left with a piston that is slightly smaller and leaks more than desirable.
  I am pleased my Aluminum piston runs better than stock but eager to try a Graphite piston.
  The homemade aluminum piston is on top, stock brass is the lower piston.



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