[white-lightning]

Here are the spec from K&N

Part HP-2009 Product Specifications
Product Style: Oil Filters
Height: 5.08 in (129 mm)
Outside Diameter: 2.99 in (76 mm)
Thread Inside Diameter: 0.75
Thread Number: 16.00000
PSI Relief Valve: 11-14
Anti Drain Back Valve: Yes
Style: Canister
Weight: 0.8 lb (0.3 kg)
Product Box Length: 3.15 in (80 mm)
Product Box Width: 3.15 in (80 mm)
Product Box Height: 5.14 in (131 mm)

Now my question is about the relief valve. I know the oil pressure in my car is suppose to run higher than the 11-14psi at which this valve opens. When does this valve open, no way does it open at that psi otherwise it will never filter?

 

[madmatt2024]

That opening pressure refers to the pressure difference between both sides of the filter medium. For example, if the filter is clogged enough for the pressure on the outside of the filter element to be 11-14psi over the pressure on the inside then the valve will open.

 

[white-lightning]

Okay that sounds right. I was just wondering what the heck that was about.