The base inlet holes aren't a "bottleneck" to flow. Tbe media is much more restrictive to flow. Even though it might look like the inlet holes are restrictive, the dP difference across the base plate hole design difference is minor.
Fram Endurance / Walmart End of Life ?
- Thread starter ChrisD46
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But as seen, many get the warm fuzzies from seeing lots of inlets and the larger they are the better that feeling. Newest ACDelco vs previous ACDelco with the auxiliary plate a great example. Very little doubt media the same, but main comment seen for the new is 'flow is better.' Tough to convince some, when it comes to filter inlets, their eyes don't tell the whole story.
A properly designed bypass valve spring can be placed on the INSIDE of the filter cylinder and not take up any more space. This is the case with the FRAM Endurance.
And many other designs—filtech/Roki; mahle tennex, too IIRC.
Yeah, not many people can look at something like the base plate (or center tube) holes and know what the dP will be without actually running the numbers. Of course seeing larger and more holes does give someone the "warm fuzzies", but it totally deceiving. For instance, I ran the dP vs flow numbers for cold (500 cSt) and hot (15 cSt) oil on a Fram XG3600 that has 8 holes that are only 0.20 inch in diameter. Compared to some other base plate hole designs, the XG3600 looks "flow restrictive", but there really isn't much flow restriction on the base plate. The center tube has even less dP vs flow. The media is the main contributor to flow restriction.
Here's the results of the calculations. The oil pump would be way into pressure relief in the cold oil case, so the flow through the filter and oiling system should be well below 10 GPM. With hot oil, even at 10 GPM the dP across those "visually tiny" holes is only 1.5 PSI. The PD oil pump doesn't care.
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More and bigger holes = more and better flow
Thanks for the heads up, picked up a case of 12 just incase.
I run a cartridge filter and these have been great.
I run a cartridge filter and these have been great.
Not really, the dP is low, and the difference between filters is even lower, so it doesn't matter to a PD oil pump. At PD oil pump is used in and oiling system for a good reason.
Still available at Walmart on line...no issues.
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Not flow volume but flow dispersal, like the Toyota N1 base went to long oval shaped holes from round holes. In practice it seems to make no difference, but clearly there is a difference or Toyota, Denso really, wouldn’t bother with the change.
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I agree with you, it's difficult to find quality filters right now. In my opinion, the new Mobil 1 filters that recently came out are the new ticket. Running one now. Great construction, about $11 at Walmart.
The new Mobil 1 made in Asia is basically the same as all the similarly made brands under the PGI umbrella (but Mobil is not under PGI). The new Mobil 1 is under Highline Warren, and the Mobil 1 use to be under M+H before that.
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Yes, I used to avoid them while they were Mann+Hummel. I ran Wix for awhile, but when those started having issues, I stopped buying M+H filters in general.
dP vs flow through the base plate will be proportional to the size and number of holes in the base plate. The base plate hole change Denso made only befits slightly if there is more total flow area as a result, maybe they reduced the dP by 0.5 PSI at high flow. Oil distributed after the oil goes through the base plate is just fine with a large gamut of options of base plate hole designs. Fluid always flows from a higher to lower pressure regions, and that's what makes it distribute.
Because Wix also became M+H owned. Why NAPA also dropped M+H supplied filters under the NAPA label.
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I know, that was my point.
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The oil is distributed more evenly with the slots. Less oil turning and hitting the sides of pleats rather than straight on. The oil streams are wider. I don’t think Denso was thinking about DP at all.
Fram seems to be trying the same thing with an abundance of holes on some filter bases.
Every engineer that designs an oil filter is thinking about dP of the base plate, media, center tube and bypass valve. ISO 4548 even has sections that the dP of each filter element to be measured. There is zero evidence that "lack of oil distribution" is a problem with any base plate hole design. The main reason is to fool people in to believing the filter "flows more" by seeing more and larger base plate holes, and to gain a hair less dP across the base plate. As already shown in this thread (post 45), even a Fram with visually small holes only has around 1.5 PSI of dP at 10 GPM with 15 cSt oil viscosity. If it had more and larger holes, the dP might go down to 1.0 PSI at 10 GPM.
This 5/16's ball passage is more than enough that feeds my Ford 2.3 duratec, hard to believe but true, this passage is large enough to feed a V-8, makes me laugh when people look at oil filters and think the holes are too small or there is not enough of them. The two ports are hooked to a highly flow restricted bypass filter.
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I wasn’t talking about baseplate pressure changes. The oil is dispersed more evenly and directed at the pleats more square on with slots or oval holes or plenty of any shaped holes. Much better imo.
There are so many fittings and pressure changes in an engine, base plate change in pressure isn’t going to be one they worry about. In fact many oil filters meet the base plate spec, all of them actually. It only needs total holes to be bigger than the outlet pipe and there is no problem.
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