Quote Originally Posted by dvldoc View Post
This is the basic flow of a oil filter. The small holes on the outside are the in, the center is the out. The bypass valve is on the top, if the filter get's clogged it pushes down on the filter element and blocks off the in so basically what's in your pan is what is circulating. A lower value BPV setting just means it will protect you from a clog sooner or a oil pressure spike due to lack of flow in the filter. Being a tropical climate unless you neglect the heck out of your oil changes it should never clog.

On the mann filter, the upper part has this spring and hole with rubber flaps pushing against the spring.

From my understanding, if the filter is clogged/ pressure is more than the BPV setting, that upper valve will open. This is contrary from closing/ blocking the inlet which you described causing totally blocked inlet and "no flow".

AFAIK the lower part is where the anti-drain back rubber is, same with BPV it is unidirectional and acts only when engine is stopped-when pressure is coming from the outlet going to the inlet (oil flow by gravity)..

I'L do some research on this but im completely sold out with fleetguard.. The lower BPV setting would not matter to me now because i change oil every 10k. Here's what i got, its the real deal but no box, just blister pack. Deym cheap, the FS 1/4 the price of OEM.