Don't some heavy duty diesels have a secondary 'bypass style' filter integral to their main oil filter? Or am I making stuff up...
K&N 171 - Forum Article in Response To Their Oil Filter Performance For Harley’s
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Don't some heavy duty diesels have a secondary 'bypass style' filter integral to their main oil filter? Or am I making stuff up...
Who makes this imaginary 5 micron high efficieny filter for H-D? Any one look at the media under a scope? (While I was typing @Sayjac answered)
Moot points on wear and particle size. With std efficiency filter by the time the bearings are shot the engine will need a refresh anyhow. But I don't aspire to the 300k club in passenger car gasoline engine like some do here.
Moot points on wear and particle size. With std efficiency filter by the time the bearings are shot the engine will need a refresh anyhow. But I don't aspire to the 300k club in passenger car gasoline engine like some do here.
You keep trying, I'll give you that. You're not correct but you are persistent.
The main bone of contention for me, also, as a specified diametrical clearance is typically < half of the running clearance. I also think the beta on the high e HD spin on is erroneous. I will choose flow over efficiency on small filters, but not to the extent of a "screen door" filter.
The article reads as if written by an experienced and knowledgeable Expo Booth sales rep, but not K&N Sr. lead engineer. I have read worse responses. lol.
- Ken
Another good write up that explains the importance of flow vs efficiency balance. There are exceptions of course but still good information. There's always a balance between efficiency/flow/holding capacity/bypass pressure. That's the facts & that's what I read here. You can't just haphazardly throw any performance specs randomly, between those perimeters, at a filter is my point.
What happens when you are attempting to classify a filter with poor filtering efficiency as superior.
Flow is about as big a non-entity as you can have in a passenger car engine. No commercially available filters that are proper for a vehicle have a problem with flow.
That I don't know. I would not be surprised if they did.
Consider a stretched out row of pleats, 75% could be standard oil filter pleats (with as many pleats as the normal filter would have) and 25% could be submicronic. Simple and easy to make. Even if the submicronic pleats clogged fully, the overall operation of the filter would simply be exactly that of a conventional filter.
Not making it up. Coarse filter is full flow. Bypass filter is on polishing duty.
Re: Bold part above. Yes, if the oil filter engineer does it correctly. It's more challenging to obtain a high mark on all of those parameters at the same time of course. But here's the clincher ... hardly any information from the filter supplier or even decent 3rd party sources will divulge what the dP vs flow performance of the their filters. So someone buying a filter has zero idea what the flow performance is unless they see some decent test data.
The writer of that article is trying to conclude (see quote below) that a more efficient oil filter will not hold as much debris and therefore he goes down the "flow over efficiency" rabbit hole, which is an erroneous conclusion since we all know some very high efficiency oil filters have "high flow" (meaning low dP vs flow) and high holding capacity. But he's trying to equate efficiency to flow, which is a misconception that a lot of people latch onto. The flow resistance of the filter in the engine's oiling system is minor compared to the rest of the oiling system (kschachn touched on that in post 26). The oil filter is typically around only 1/15th of the total flow resistance of the engine system. There is no "the tradeoff is flow" unless the filter is so clogged and restricted that it causes major pump slip on a worn-out pump, or makes the pump hit pressure relief.
"When you are talking about filtration, whether it be oil or air, there is a balancing act that has to be performed to ensure your engine gets the protection it needs while giving your engine the most flow possible. Unfortunately, when the focus is an oil filter that is catching extremely small particles at a high percentage, the tradeoff is flow rate. This put the consumer in a "Catch-22" situation. Do you use a filter with the most efficient media at the smallest particle rating, and have the bypass open letting unfiltered oil through the system? Or do you have a filter that does not filter as small a particle size, but filters more of the oil for a longer period of time?"
The way around that tradeoff is to add more media. Longer filter, deeper pleats, more pleats, etc. With more filter area you can offset the pressure increase of a move to higher filtration media. That keeps you from incurring any additional bypass penalty.
Then the tradeoff is filtration vs cost, size, and weight.
Good idea, I am going to ask, see what they say.
I appreciate your thoughts on this. I thought the 95.8 at 5um was pretty amazing, but I question the reality of that statement.
Sure would be nice if all the manufacturers had to publish their performance specs so the consumer can evaluate and make the “best decision.”
It’s like the maze of a mortgage loan; with all the various costs for financing, i.e., loan fees, title fees, escrow fees, appraisal fees, inspection fees, etc., without the costs being factored in and expressed in the form of APR (annual percentage rate), a consumer has no way of comparing options.
I hate when there is a lack of transperancy in the marketplace of products.
Companies just expect the consumer to trust what they say; and as a former President said, “trust, but verify.” A great statement.
It’s like the maze of a mortgage loan; with all the various costs for financing, i.e., loan fees, title fees, escrow fees, appraisal fees, inspection fees, etc., without the costs being factored in and expressed in the form of APR (annual percentage rate), a consumer has no way of comparing options.
I hate when there is a lack of transperancy in the marketplace of products.
Companies just expect the consumer to trust what they say; and as a former President said, “trust, but verify.” A great statement.
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Yes, even if they all just had the % efficiency at 20u on the box, it would nice and make it easy for comparing filters.
Yes-if only there was a way to have 2 layers of full synthetic media, with the oil passing through the lower efficiency first, and the higher efficiency second. With plenty of thickness for depth filtration & the ability to hold contaminant in the media so they couldn't wash out under high flow bypass events! They could call it Stratapore! Or Donaldson Blue! Or the (unfortunately gone, somewhat flawed) OG Ultra!
In series, you get the restriction of both, unless you add square footage of filter face area to bring velocity through the media (and thus, pressure drop) down.
Donaldson isn't the only one building gradient filtration media. In the world beyond $10 engine oil filters there's some fun stuff to be had.
