<VV> high performance oil pressures

[BobHelt at aol.com]

In a message dated 4/17/2010 9:45:04 P.M. US Mountain Standard Time,  
Markpowhatan at aol.com writes:

I read  much about using high volume oil pumps vs. stock  pumps, but I am  
wondering if using such would cause the oil  filter  bypass  valve to open, 
and 
not filtering all the oil.  Is this  scenario  possible or is the pressure 
still going to be equal on both sides of   the filter, keeping the valve 
from 
needing to open?  I just thought  about  this since I'm in the middle of 
having a engine rebuilt. --  Newbie here  just curious...Mark  63 Spyder  
in  
Virginia



hello, Newbie,
Thanks for your question. Re: high volume oil pumps.....
 
I doubt that there will be any such problems with a high volume oil pump.  
Here's the story. High volume oil pumps do not change the maximum oil 
pressure  from that of a stock pump. Therefore there should not be any such 
problem as you  describe. What these high vol pumps do is increase the pressure at 
less than  maximum so as to overcome excess oil leakage due to large 
bearing clearances.  And the reason for using these pumps is mainly to prevent the 
OIL LIGHT from  illuminating at idle speeds. Otherwise these pumps cause 
problems by causing  excessive wear on the crankshaft gear that drives the oil 
pump during very low  temperatures when the oil is very thick. In addition, 
during higher and normal  temperatures these pumps tend to churn the oil 
excessively by causing oil to  recirculate from the pump and back to the sump 
when the oil pressure valve is  open. This tends to heat the oil excessively.
 
Bottom line is DON'T USE  a high vol pump unless you really need one. 
 
Regards,
Bob Helt