Guess if you are defining "filtration rate" as the measure of oil not bypassing, then yeah. But without some super controlled testing, nobody can accurately determine exactly which filters will bypass and by how much under all driving conditions. For one thing, all we have is a manual spec showing the pump flow rate, but AFAIK, nobody has actually verified with instrumentation of the oiling system on an actual vehicle if it is flowing that much flow through the filter and oiling system in real world use.
Subaru OEM vs. M1 vs Fram Ultra vs. Fram Endurance for Subaru 2.5 DI (2023) and 2.5 PI (2013)
- Thread starter NO2
- Start date
I assume that by "filtration rate", you mean flow rate. An absolute efficiency of 40-50 micron seems to be pretty much standard for OE filters from various makes, and most aftermarket cellulose filters as well, so Subaru isn't doing anything different there. They specify a bypass pressure setting for their filters that allows full flow without bypassing, just like any other car manufacturer does. Subarus just happen to require a high bypass pressure setting to achieve that due to high oil flow rates. They could have instead specified a more typical bypass pressure and used a filter with more media area, so that there would be less pressure drop for a given flow rate, but they opted for a high bypass pressure instead, maybe due to filter size constraints.
I use a Baxter adaptor (basically an anti-siphon valve) so I get to use a larger Fram Ultra/Titanium 10575, which also has a higher bypass pressure (16-28psi). More filter area + good flowing Ultra + higher bypass pressure = less times being in bypass.
OVERKILL
$100 Site Donor 2021
The factory service manual shows some insanely high oil pump flow specs - been discussed a few times in various threads over the years. But as I mentioned, has anyone verified that max specified oil volume flow actually goes through the oiling system. It's hard to believe the oiling system see that high of flow, and as I pointed out before it would mean the 5 qt sump is cycled every like 12 seconds through the engine. Crazy flow.
OVERKILL
$100 Site Donor 2021
A stock LS3 pump is 6.8gpm, which is 27.2 quarts per minute or 0.45 quarts per second, which is 5 quarts in 11 seconds.
Apparently, the stock 5.7L HEMI (MDS) oil pump flows 5.08gpm @ 2,000RPM.
So, with that context, how does that, if it does, change how we view this Subaru stuff?
I'd have to go dig up the discussions. Some Subarus are specing some crazy flow like around 15-16 GPM at redline. So maybe it was more like one sump volume of flow through the engine about every 5 sec at redline. Just recall it was pretty nuts.
OVERKILL
$100 Site Donor 2021
Be interested to see it, the highest volume LS3 pump I saw was 9.3gpm and is recommended for wide-clearanced all-out race engines running turbo's with massive external oil coolers and spun beyond 8,000RPM.
I think member @twX posted the Subaru service manual specs. Maybe he can link to his post(s), or post them here again.
OVERKILL
$100 Site Donor 2021
Found it:
Which is:
600rpm: 1.225gpm
5,000rpm: 12.42gpm
5.7L HEMI pump:
500rpm: 1.90gpm
2,000RPM: 5.08gpm
Not sure how that scales, but I'd assume the HEMI pump is going to be higher volume at 5,000RPM.
I think there was another Subaru engine pump that speced more than 12.4 GPM.
If the pump output remained linear on the HEMI, it would be 5000/2000 x 5.08 = 12.7 GPM. It probably isn't perfectly linear though due to some slip.
Last edited:
OVERKILL
$100 Site Donor 2021
Well, perhaps he'll chime-in then
Interestingly, the gpm rating for the LS3 pumps don't list RPM, so I have no idea at what speed that is achieved.
Here's the discussions.Well, perhaps he'll chime-in then
Interestingly, the gpm rating for the LS3 pumps don't list RPM, so I have no idea at what speed that is achieved.
Post in thread 'Check out my magnets on my oil filter' https://bobistheoilguy.com/forums/threads/check-out-my-magnets-on-my-oil-filter.366342/post-6424467
Subaru uses more than one oil pump, I run the 11mm pump (OE was 10mm) in my EJ, 63 ltr/min @ 6000 (16.6 gal/min)
OVERKILL
$100 Site Donor 2021
Of course you run the highest volume one in the table, lol.
So it's 1.69gpm at 600RPM, closer to the HEMI's pump than the 10mm one.
At what RPM do you end up on the relief?
AFAIK the only time it goes into relief so far is at cold start under 40f, it is 85-95psi, with the oil (A3/B4) at about 200f it sees about 65psi at 5000. The engine only has 3,500K on it since I built it so it has not seen hard use.
I went with the 11mm because the 10mm is known to have lower oil pressure at hot idle not enough to trigger the oil pressure light which is 2.5lb and poor flow to the heads
I went with the 11mm because the 10mm is known to have lower oil pressure at hot idle not enough to trigger the oil pressure light which is 2.5lb and poor flow to the heads
I would stick with the "original" original. ie. the black. old blue is usual junk fram. new blue one is?
The Toko Roki is a good filter but you need a filter cup wrench which is an odd ball size 66.5mm which is not available in local stores.
A universal wrench will remove it but on the ring of fire engines you really need the cup (anyone that has one knows why). The ones that fit the wix and others are a little too small. This one fits them perfectly.
chadstoolbox.com
A universal wrench will remove it but on the ring of fire engines you really need the cup (anyone that has one knows why). The ones that fit the wix and others are a little too small. This one fits them perfectly.
BETA 014930315 1493AL 66,5-L14-OIL-FILTER WRENCH
Beta Tools of Italy are premium manufacturer and racing spec tools. ChadsToolbox is pleased to present this BETA 014930315 1493AL 66,5-L14-OIL-FILTER WRENCH at the lowest prices in North America
chadstoolbox.com
Similar threads
- Locked
- Locked