Thread: Building an engine run stand.
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Old Tue, June 7th, 2022, 09:19 PM
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Quote:
Originally Posted by Power Hungry View Post
What did you end up running for Ring End Gap? Normally on a 4.360" bore with factory pistons and rings, I'd use about .025" - 0.028" for compression rings (maybe 0.028" - 0.030" on the 2nd ring) and .018" - 0.020" for oil ring.

For aftermarket stuff I just use whatever they recommend, especially for hypereutectic pistons. The expansion rate on those are slightly different then regular aluminum slugs.

*Technically", some specs only call for 0.004" per bore inch, so in those cases a 0.017" end gap would be considered acceptable. At the end of the day, I'd rather be a tad larger gap than too small. As someone mentioned:

If the gap is too big, only you will know. If the gap is too large, EVERYONE will know!

I'll be running .029" due to the 4.442" bore and the formula of .0065"/in. on run of the mill "rebuilder" cast pistons.

Better safe than sorry.
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Tuning, PCM flashing, and burning chips for 7.3s since 2008. Repairing all aspects of 7.3L Powerstrokes for 25 years.
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