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Rod Bearing deviation of +/- 5 "g", What is "g"??
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10-21-2019, 07:42 PM | #1 |
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Rod Bearing deviation of +/- 5 "g", What is "g"??
In the TIS info manual, they list the connecting rod tolerances (without bearing) as 53,600 ... 53,616 as "mm" Millimeters. Which I get, but then the "Permissible total deviation of connecting rods in one engine (without bearing shells" is +/- 5 with "g" as the unit of measurement. What is a "g"???
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10-21-2019, 09:38 PM | #3 | |
Captain
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Quote:
I already got a replacement rod from a friend but it is just a little out of round for my liking. the sizes I got from measuring the others at 3 places were typically: Rod #1 was 53.467, 53.441, 53.594 mm Rod #2 was 53.467, 53.518, 53.569 mm Rod #3 was 55.885, 53.213, 53.340 mm (this one is obviously bad) Rod #4 was 53.619, 53.594, 53.594 mm Rod #5 was 53.518, 53.467, 53.594 mm Rod #6 was 53.594, 53.341, 53.314 mm Then the one my friend gave me measured: 53.797, 53.441, 53.645 mm |
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10-21-2019, 10:36 PM | #5 |
Captain
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I don't have a scale but I don't think weight is as critical as people think as long as you are using identical rods and pistons. I recently rebuilt my N54 in another car and swapped in a whole other used piston and rod I bought off eBay to replace my bent #3 rod. I have full bolt-on's and I run the car hard with no problems. I can see that being an issue if you swap in one different variation of an engine that may have a slightly different piston/rod weight. My issue right now is the big end size and diameter on the N55 I am rebuilding now.
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10-22-2019, 08:46 AM | #6 | |
Colonel
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Quote:
It's just important to understand all these things when slapping back together a blown up engine lol. |
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10-22-2019, 11:49 AM | #7 |
Captain
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I definitely understand how important balance and clearances are to something that has hundreds of parts flying around at several thousand RPM. :-)
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