If you have an engine with somewhat small oil filter (especially the stubby little BRZ/GR86 cars) or merely a Honda or similar with a small Fram 7317 size (M1-110), I think there may be a performance increase as well as a convenience increase that would justify the hassle of relocation to allow a larger filter that is easier to service. Larger filters have lower face velocity and perform better given the same media and flow rate.
This post is about 1)what remote options might be actual performance improvements, and 2) how to actually plumb such a thing so that you don't screw up the overall performance.
One Remote Filter Option to illustrate:
The Donaldson SP15 seems small enough it would be fairly easy to package on your vehicle:
The filter head is available with -8 or -12 SAE ORB ports (no leaks!) in addition to the why-do-they-still-exist NPT ports. -12 gives you all kinds of options for bypass ratings.
The 30gpm flow rating and 100psi element collapse rating should be quite sufficient (since we'll use a version equipped with bypass, it should never see anything near 100psi delta on the media).
Oh, and the efficiency?
That's 99.9% efficient at >SIX MICRONS. At least for that one version of the element. But perhaps you think that might be too restrictive? They have 11 micron and 23 micron elements as well (all ß1000 per ISO16889). That 23 micron element looks like a real winner for a full-flow option.
So there's one option-- a $50 filter head with some exciting, ultra-efficient spin-on options for filtration. But now they hard part, how do we build a system around this so we don't create excess oil pressure delay, risk oil starvation, or or otherwise reduce the reliability? It's counterproductive to improve filtration while reducing reliability.
One caveat: HYDRAULIC FILTERS HAVE NO PROVISION FOR ANTI-DRAINBACK.
Plumbing and Integrating a remote filter
Messing with the oil system should never be undertaken lightly. There are MANY devils hiding in details. They key thing here if you relocate the filter is to do it in such a way that you aren't making other parts of the oiling system worse in performance.
In a conventional relocation setup (OEM filter replaced with adapter plate that routes flow to a remote head), you will have a good bit of plumbing to the remote filter. This plumbing will (or should be) drained when the filter is serviced. Which then presents the problem of how do you prevent excessive oil pressure delay waiting for the system to re-prime? It's one thing to prefill a filter. It's quite another to prefill a run of plumbing also. It's somewhat difficult to do. It seems to me just a straight up relocation is likely to cause excess oil pressure delay at a service event.
Even with no air in the filter, remote mounting slightly delays oil pressure rise because it's "less stiff" hydraulically (lower bulk modulus).
So-- one of the first decision points in our schematic is: are we *relocating* the filter or are we adding a filter in parallel? I think it's clear enough that having the filter in parallel is desirable. This lets bring that flow in or out of the schematic based on a control input like temperature or pressure. Oil pressure delay is absolutely critical to durability in start/stop applications. Merely relocating the filter (even if it's an larger, more efficient filter) means more oil pressure delay; that is not a good thing.
So we need a filter in parallel. It turns out that's harder to do than it sounds. The standard sandwich adapters have the ports in series with the filter element. Which means you have to do your bypassing in the plumbing.
Which means tees on the outlet ports and making a hard bypass.
So maybe we start with an adapter like this nice quality piece from Setrab:
For our PCMO purposes, -8 JIC is plenty of flow capacity in the outlet ports. This adapter routes oil through the external ports BEFORE sending it to your filter. So if we want quick oil pressure response, we need to tie these ports together on some run tees with a jumper that allows oil a very short path back. And on the rest of the run, we need to find a way to force oil to take the "jumper" instead of go to the remote filter until we have oil pressure.
But how do we force the oil the take the shortcut when when we first start, then cut over to the remote filter once we have pressure? A simple inline check valve on the hose to the remote filter won't do it. It will essentially cause all flow to bypass the remote filter all the time because once pressure is built, it acts backwards on both the bypass and the remote filter, thus assuring the bypass is always preferential enough that the check valve never opens, even if it's only 5psi.
Thus, it seems pressure control is the realm of hydraulic cavities and sophisticated pressure controls that are not realistic for a simple oil filter project.
What if we went to a thermostatic bypass like this one design for oil coolers?
This adapter has a 180F activated thermostat. Below that temperature, the oil is never routed through the external ports. That means every cold start would essentially duplicate perfectly the OEM spin-on configuration with essentially zero additional oil pressure delay. Oil is then routed to the parallel filter only once its up to temperature.
I think this is likely the best option for adding an extra, higher-performance filter. Temperature activation means a cold start never suffers from excess oil pressure delay. And if you should happen to restart with hotter oil, the external loop has already been pressurized and primed, so the oil pressure delay on a hot restart is ALSO minimal and similar to you'd have with the OEM spin-on setup.
If you do pressure-based control instead of temperature, you end up with a ton of extra plumbing and complexity. And of course, more plumbing and complexity are opposed to reliability.
With the thermostatic sandwich adapter, you have minimal plumbing-- an adapter, your original spin-on filter, a remote head and two hoses to plumb it.
Now, what happens if the thermostat on the adapter fails? Well, if it fails closed, you'll essentially just have your stock spin-on setup. If it fails open, you'll be constantly sending oil to your remote filter head. It's easy enough to diagnose the failed-close option when your remote filter never gets warm. The failed-open fail mode would be harder to troubleshoot.
So-- a thermostatically controlled filter filter sandwich adapter that, once it cracks at 180 degrees, routes oil to the high-efficiency remote filter. It's sort of a middle ground between full flow and bypass filtration. Because the oil is already warm and thin before it goes to the remote filter, you can probably get away with the 11 micron element. And if the element should become plugged? Well, we opted for the 5psi bypass, so it just bypasses and you're left with "only" the normal spin-on you've trusted already. Or you could use the 23 micron element and get efficiency that is a nice upgrade to many spin-ons while still flowing very well and having excellent real world efficiency.
Seems pretty straightforward? What do you think? I'm not really interested in a typical bypass setup and I don't buy into toilet paper filters that waste TP and do slow-motion oil changes with all the "top offs." (this is really just a series of short interval partial changes).
This post is about 1)what remote options might be actual performance improvements, and 2) how to actually plumb such a thing so that you don't screw up the overall performance.
One Remote Filter Option to illustrate:
The Donaldson SP15 seems small enough it would be fairly easy to package on your vehicle:
The filter head is available with -8 or -12 SAE ORB ports (no leaks!) in addition to the why-do-they-still-exist NPT ports. -12 gives you all kinds of options for bypass ratings.
The 30gpm flow rating and 100psi element collapse rating should be quite sufficient (since we'll use a version equipped with bypass, it should never see anything near 100psi delta on the media).
Oh, and the efficiency?
That's 99.9% efficient at >SIX MICRONS. At least for that one version of the element. But perhaps you think that might be too restrictive? They have 11 micron and 23 micron elements as well (all ß1000 per ISO16889). That 23 micron element looks like a real winner for a full-flow option.
So there's one option-- a $50 filter head with some exciting, ultra-efficient spin-on options for filtration. But now they hard part, how do we build a system around this so we don't create excess oil pressure delay, risk oil starvation, or or otherwise reduce the reliability? It's counterproductive to improve filtration while reducing reliability.
One caveat: HYDRAULIC FILTERS HAVE NO PROVISION FOR ANTI-DRAINBACK.
Plumbing and Integrating a remote filter
Messing with the oil system should never be undertaken lightly. There are MANY devils hiding in details. They key thing here if you relocate the filter is to do it in such a way that you aren't making other parts of the oiling system worse in performance.
In a conventional relocation setup (OEM filter replaced with adapter plate that routes flow to a remote head), you will have a good bit of plumbing to the remote filter. This plumbing will (or should be) drained when the filter is serviced. Which then presents the problem of how do you prevent excessive oil pressure delay waiting for the system to re-prime? It's one thing to prefill a filter. It's quite another to prefill a run of plumbing also. It's somewhat difficult to do. It seems to me just a straight up relocation is likely to cause excess oil pressure delay at a service event.
Even with no air in the filter, remote mounting slightly delays oil pressure rise because it's "less stiff" hydraulically (lower bulk modulus).
So-- one of the first decision points in our schematic is: are we *relocating* the filter or are we adding a filter in parallel? I think it's clear enough that having the filter in parallel is desirable. This lets bring that flow in or out of the schematic based on a control input like temperature or pressure. Oil pressure delay is absolutely critical to durability in start/stop applications. Merely relocating the filter (even if it's an larger, more efficient filter) means more oil pressure delay; that is not a good thing.
So we need a filter in parallel. It turns out that's harder to do than it sounds. The standard sandwich adapters have the ports in series with the filter element. Which means you have to do your bypassing in the plumbing.
Which means tees on the outlet ports and making a hard bypass.
So maybe we start with an adapter like this nice quality piece from Setrab:
For our PCMO purposes, -8 JIC is plenty of flow capacity in the outlet ports. This adapter routes oil through the external ports BEFORE sending it to your filter. So if we want quick oil pressure response, we need to tie these ports together on some run tees with a jumper that allows oil a very short path back. And on the rest of the run, we need to find a way to force oil to take the "jumper" instead of go to the remote filter until we have oil pressure.
But how do we force the oil the take the shortcut when when we first start, then cut over to the remote filter once we have pressure? A simple inline check valve on the hose to the remote filter won't do it. It will essentially cause all flow to bypass the remote filter all the time because once pressure is built, it acts backwards on both the bypass and the remote filter, thus assuring the bypass is always preferential enough that the check valve never opens, even if it's only 5psi.
Thus, it seems pressure control is the realm of hydraulic cavities and sophisticated pressure controls that are not realistic for a simple oil filter project.
What if we went to a thermostatic bypass like this one design for oil coolers?
This adapter has a 180F activated thermostat. Below that temperature, the oil is never routed through the external ports. That means every cold start would essentially duplicate perfectly the OEM spin-on configuration with essentially zero additional oil pressure delay. Oil is then routed to the parallel filter only once its up to temperature.
I think this is likely the best option for adding an extra, higher-performance filter. Temperature activation means a cold start never suffers from excess oil pressure delay. And if you should happen to restart with hotter oil, the external loop has already been pressurized and primed, so the oil pressure delay on a hot restart is ALSO minimal and similar to you'd have with the OEM spin-on setup.
If you do pressure-based control instead of temperature, you end up with a ton of extra plumbing and complexity. And of course, more plumbing and complexity are opposed to reliability.
With the thermostatic sandwich adapter, you have minimal plumbing-- an adapter, your original spin-on filter, a remote head and two hoses to plumb it.
Now, what happens if the thermostat on the adapter fails? Well, if it fails closed, you'll essentially just have your stock spin-on setup. If it fails open, you'll be constantly sending oil to your remote filter head. It's easy enough to diagnose the failed-close option when your remote filter never gets warm. The failed-open fail mode would be harder to troubleshoot.
So-- a thermostatically controlled filter filter sandwich adapter that, once it cracks at 180 degrees, routes oil to the high-efficiency remote filter. It's sort of a middle ground between full flow and bypass filtration. Because the oil is already warm and thin before it goes to the remote filter, you can probably get away with the 11 micron element. And if the element should become plugged? Well, we opted for the 5psi bypass, so it just bypasses and you're left with "only" the normal spin-on you've trusted already. Or you could use the 23 micron element and get efficiency that is a nice upgrade to many spin-ons while still flowing very well and having excellent real world efficiency.
Seems pretty straightforward? What do you think? I'm not really interested in a typical bypass setup and I don't buy into toilet paper filters that waste TP and do slow-motion oil changes with all the "top offs." (this is really just a series of short interval partial changes).
