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Old 10-24-2013, 10:10 AM
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Stretch Stretch is offline
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Join Date: Sep 2009
Location: Somewhere in the Netherlands
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Quote:
Originally Posted by 97 SL320 View Post
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Remove material from the green areas _TOWARDS_ the crown, don't increase the diameter.

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Quote:
Originally Posted by 1project2many View Post
...

What 97 SL320 is referring to is the factory's balancing method. It's a single cut to save time and money. If you look at the difference in thickness of the pin boss between that machined area and the portion toward the center of the piston, it appears substantial. I wouldn't be afraid to continue the factory operation. I would still try to identify where the differences are between pistons before metal removal.

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Here's a quick sketch showing why cutting into the green line area can't be done for long



Apologies for the lack of ISO standard drawing practices!



^^^ This rough sketch shows a quarter cross section of the piston - I hope it is understandable...
Attached Thumbnails
Engine builders' advice req'd - removable piston weights?-sketch-m102-piston-cross-section.jpg  
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