Originally Posted By: 440Magnum
Originally Posted By: crazyoildude
i think purolator cut down on torn filters by slowing down the oil flow using super small oil holes on the center tube.... Yeah i know i sound like a broken record but it is what it is.
It is what it is, and its not an issue. The math doesn't add up for it to be an issue- take the cross section of each "super small" hole, multiply by the total number of holes in the center tube, and you'll still get a total area that's bigger than the cross section of the threaded filter mounting tube that all the oil has to flow thru on the way back into the engine. Small holes = better media support. The other extreme (big holes) is E-core, and nobody likes THAT either!
If the cross section of all the louvered slits adds up to more than the cross section of all holes in the old center tube design, then the velocity of oil through each slit will be less than the velocity of the oil through each hole in the old center tube design.
That would help to more evenly distribute and slow down the oil flow velocity through the media right next to the louvered openings in the center tube.
I don't think the Purolator tearing problem was due to the center tube design with the round holes since they never had a tearing issue until something else changed, like the media brittleness and the wide pleat spacing near the seam - which I think was the main problem. Purolator could have changed the center tube design to help reduce the chances of tearing by trying to distribute the flow through the media a little better.