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Old 03-04-2012, 06:26 AM   #15 (permalink)
bandit86
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Quote:
Originally Posted by oil pan 4 View Post
A high vacuum would be bad. Having about -5psi or 10''Hg is ideal.
Word on the street is a high vacuum pulls oil away from wrist pins. It would also cavitate the oil pump, before pressurized hydraulic oil tanks came along aircraft above 30,000ft could have their hydraulic pumps cavitate do to lack of absolute pressure on the return side.
You might be able to go as high as 15''Hg to 20''Hg on a non racing application. Monkeying with your oiling system is playing with fire, I took a risk by running low tention oil rings on my diesel and it seems my reasoning for needing standard or high tension oil rings was sound. (diesels dont need them because they don't draw much vacuum)
I don't see how vacuum in the oil tank would cause cavitation. Oil pumps turn at a surprisingly low speed, I watched a giant v8 diesel from a semi with the valve cover removed and the oil trickled from the valve area at best. The rest of the system relies on pressure, and will not splash much oil.
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