Why is one 340 connecting rod bronze color?

100_1331.JPG The information supplied in post #35 has it's place in the industry, what that is all referring to is for use in the motorcycle or snowmobile engine manufacturing, where "surface hardness of Rockwell C of 60-63" needs to be achieved for use with "roller surface" type bearings.
What's going on here is simply put in post #25 a last attempt to be able to use a rod before it's turfed.

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