Senior Clinician
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Post by jomama0867 on Feb 26, 2023 6:56:38 GMT -6
I recently decided to upgrade my 139QMB BBK from a 47mm to 52mm cylinder and head. After installing, I discovered a noticeable drop in compression. My question is this . . . has anyone seen a piston with this surface (on the left) ![???](//storage.proboards.com/3059616/images/uQfospbezE7IcMUG1AtY.gif)
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Senior Clinician
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Post by jomama0867 on Feb 26, 2023 6:58:02 GMT -6
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