Thread: Dry or Wet Sump
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Old 10-06-06, 06:13 PM   #14 (permalink)
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jac mac
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Smile Re: Dry or Wet Sump

Quote:
Originally Posted by YerDugliness
For all builds, Jac? Would this be single holes directly above the pin ends or a number of holes around the circumference, as some do for the top compression ring?

Thanks for this tip, BTW. You really are a wealth of information!!!

Doug
You have to take the application into account Doug. For example in the 3.25"/3.40" SBF stroker versions where the oil ring is just above or even over the pin bore it is better to drill two holes from the oilring groove to pin bore @ the 10/2 oclock positions ( where these enter the pin bore they can be connected with a small groove to allow oil to get to the top of the pin). Further holes around the ring groove simply allow oil to drain into the crankcase. Try to keep these away from the skirt thrust c/l to avoid the hole itself becoming a stress point for crack propagation.

The holes or 1/2 holes ( they only go as deep as the groove)in the top ring groove are to allow combustion pressure to access the back of the ring and increase radial ring pressure on the cyl wall. Be careful with this one as ring life can be shortened considerably.

Jac Mac
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