Easy bub, it ain't the relief valve but the check valve.  It keeps the oil
galleries from draining back into the crankcase while the engine sits.

:)

david

At 10:25 PM 4/5/2001, radish150 wrote:
>I usually use Wix filters on everything, that or mobil one synth type. So,
>my question is WHY are
>these not good enuf? Ok, so there's a relief valve, what does it do? Is it
>just designed to "let
>go" if the pressure get's too high? Ok, I'll by that, but how does this
>relate to the idea of ones
>lifters cackling with cheaper filters? Do the proper filters acutally help
>maintain a HIGHER oil
>pressure under any conditions? Come on, does anyone really know what this
>"difference" really is?

David Beierl - Providence, RI
  http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"