Forward facing filter "Important Info"

[keltalon]

This thread is absurd. While that hole may relate to your WOT pressure it has nothing to do with your head.

Okay since you feel that it's absurd then ignore this thread and read a little more about the dsm oiling system for this reason I will not waste my time addressing your questions . It obvious that you want to argue and aren't interested in a a logical explanation! because you know all about dsm and therefore are not open to to improving your car performance. Keep doing it your way bro and I will keep doing it mine , that way you are happy and I am happy, with what I have discovered! Lol

 

[SaulHudson]

Okay since you feel that it's absurd then ignore this thread and read a little more about the dsm oiling system for this reason I will not waste my time addressing your questions . It obvious that you want to argue and aren't interested in a a logical explanation! because you know all about dsm and therefore are not open to to improving your car performance. Keep doing it your way bro and I will keep doing it mine , that way you are happy and I am happy, with what I have discovered! Lol

Actually I am all for a logical explanation, that is what I want since you didn't take time to see how this worked, your logic was based on my other ofh doesn't have this hole, I don't need it, as stated earlier in this thread.
The dsm oiling system, you mean how oil pressure pushes on the position causing spring to compress and oil to bleed through the big hole back to the pan? This starts around 30 lbs on most dsm ofh. Again I'm not debating that this hole may affect WOT pressure, but bleeding oil back to the pan has nothing to do with idle head pressure.
I have no problem accepting the facts, but there are no facts to accept. You base this on stock oil pressure gauge not an actual measurable amount. I understand you say it's where mitsubishi wanted it but please point me in the direction of some literature or info on how this stock gauge works, what it measures. There is no real info, just speculation based on basic oil pressure gauge knowledge. While its probably correct we still don't know what it's measuring. Just because it measures "something" which could be pink unicorns.

I'm not here to argue, I'm here for a logical explanation on how more oil in the pan relates to higher head idle pressure, do you have one?

 

[LandSpeed-DSM]

I shared this in another oil gauge and pressure related thread a couple days ago:

A proper oil pressure gauge is a wise investment for any car, stock or modified. Spend the money on a reputable brand, and with a little forethought you can order some lines, fittings and caps you'll be able to take pressure at several spots by just moving the sending unit around as you please.

You can then check from the OFH, tee'd into your turbo feed, or the head.

When everything went back together last spring and the HX52 went on for the first time, the new oil pressure sensor was on the turbo feed with the stock gauge sender in the factory spot. So when we primed the pump with a drill we could verify pressure was reaching the turbo. Then made sure that turbo oil pressure was both steady and within manufacturer spec on the thicker oil I chose for this setup. (Cold start max, idle min, loaded min, and hot max)

After a few days to get a baseline on the turbo line, pulled the sensor and plugged the tee then moved it over to where the 1G factory turbo feed line hooks up. Used this to check on the Kiggly HLA for a few days, and the onto an open port on the OFH (Aircooled '90 OFH) to see what the actual pressure is vs stock gauge. The stock gauge might as well just a light that just turns on, off and dims or brightens a bit. Barely moves when the pressure swings 10-15psi

Then in late November when the temperature dropped into the teens over in the weeks before I put her away I would get a puff of blue smoke on letting off the throttle from high rpm. Sensor on the OFH was giving me upwards of 90-100psi, decided to check the the turbo feed which was 85psi at the same rpm. Spec hot max is ~75psi per the Holset FSM. Switched to a 5w40 from the 20w50, pressure went down but still met the minimums. Put the sensor back on the OFH and left it there.

Most decent gauge kits will cost > $100, fittings/caps maybe $50 depending on your setup. It's worth it. The only lines I bought were for the feed, which I needed anyways(old pic):

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Opening the relief valve at the pump (the source of flow and thus pressure) will drop pressure across the entire system. The drop will be greater farther down the line. That part is not really up for debate, it's the same for any fluid system and that concept applies to electrical systems to.. "Resistance."

Here's some diagrams of our oiling system with different types of OFH, notice the head is the end of the line:

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You can easily test pressure in the head through two spots, at the HLA galleys and the (1G) stock turbo feed port. Which I should mention in testing the HLA, I actually used the HLA galley and then moved to the turbo feed port.

Again, the relief is directly after the pump on these OFH, not just the 1990. It's the same principal used in several fuel systems. The pressure regulator/relief is directly after the pump to limit max system pressure.

If you drop the spring rate at the relief, you will have decreased pressure at the head and by more than what you saw at the OFH because of pumping losses.

 

[RedTalonTsi]

I'm surprised no one has any commentary on why that pin-hole is in the forward facing housing in the first place. Somewhere out there is a design engineer who decided it belonged there.
Even when that vendor chimed in all he had to say was to confirm that it's not present on other filter housings.....which begs the question......

 

[keltalon]

Actually I am all for a logical explanation, that is what I want since you didn't take time to see how this worked, your logic was based on my other ofh doesn't have this hole, I don't need it, as stated earlier in this thread.
The dsm oiling system, you mean how oil pressure pushes on the position causing spring to compress and oil to bleed through the big hole back to the pan? This starts around 30 lbs on most dsm ofh. Again I'm not debating that this hole may affect WOT pressure, but bleeding oil back to the pan has nothing to do with idle head pressure.
I have no problem accepting the facts, but there are no facts to accept. You base this on stock oil pressure gauge not an actual measurable amount. I understand you say it's where mitsubishi wanted it but please point me in the direction of some literature or info on how this stock gauge works, what it measures. There is no real info, just speculation based on basic oil pressure gauge knowledge. While its probably correct we still don't know what it's measuring. Just because it measures "something" which could be pink unicorns.

I'm not here to argue, I'm here for a logical explanation on how more oil in the pan relates to higher head idle pressure, do you have one?

Here's a quick answer it worked argue all you want modify if you choose I don't care! Lol I am satisfied with what I did. I am out of town typing on on phone but when I get back home I will talk more. Lol

 

[SaulHudson]

I shared this in another oil gauge and pressure related thread a couple days ago:



Opening the relief valve at the pump (the source of flow and thus pressure) will drop pressure across the entire system. The drop will be greater farther down the line. That part is not really up for debate, it's the same for any fluid system and that concept applies to electrical systems to.. "Resistance."

Here's some diagrams of our oiling system with different types of OFH, notice the head is the end of the line:

You must be logged in to view this image or video.

You must be logged in to view this image or video.

You can easily test pressure in the head through two spots, at the HLA galleys and the (1G) stock turbo feed port. Which I should mention in testing the HLA, I actually used the HLA galley and then moved to the turbo feed port.

Again, the relief is directly after the pump on these OFH, not just the 1990. It's the same principal used in several fuel systems. The pressure regulator/relief is directly after the pump to limit max system pressure.

If you drop the spring rate at the relief, you will have decreased pressure at the head and by more than what you saw at the OFH because of pumping losses.

This makes sense.

However, the gasketing system/ mating surface of the ffofh sends the oil coming from said hole to the bore in the gasket where oil would flow when the piston opened.

This logical explanation with a diagram makes sense why closing a relief hole effects idle head oil pressure, however it seems like a substantial.

It doesn't change that this is measured with pink unicorns on stock gauge.

 

[Sp1kE]

Wow,
I just stumbled across this.
I put in a FFF to my 2.4 build with no BS's, about 3-4 years ago.
My pressure was always super low at hot idle, and when revving it out, it would never raise how I seen other peoples.
I thought I just Eff'd something up when building the motor but I did so many changes at once when building this motor, I never thought to change the filter housing, Nor did I have room to put the original one back in.

I am going to try this, thanks a bunch!!

 

[keltalon]

I'm surprised no one has any commentary on why that pin-hole is in the forward facing housing in the first place. Somewhere out there is a design engineer who decided it belonged there.
Even when that vendor chimed in all he had to say was to confirm that it's not present on other filter housings.....which begs the question......

It's in there because mitsubishi use the same filter housing design on the single overhead mighty max truck with a head oil volume less than the dual overhead 4g63 Engine. Less volume would mean higher oil pressure at idle for the single overhead cam engine and both would be the same wot because that pressure then would be controlled by the spring inserted in the oil filter housing. Instead of redoing another filter housing for the mighty max mitsubishi drilled a relief hole in the forward facing filter to bring oil pressure within specs for the mighty max truck. That hole bleeds constantly for a dual head cam it's not good at idle Imo

 

[LandSpeed-DSM]

This makes sense.

However, the gasketing system/ mating surface of the ffofh sends the oil coming from said hole to the bore in the gasket where oil would flow when the piston opened.

Right. But, without actually measuring pressure you can't do much with that information. And every single setup will have different results on a straight up install.

That's why we can't make blanket claims about the benefits of just welding the sucker shut. It's also why I went to the "trouble" to install a proper gauge/sensor kit with the ability to move the sensor to different spots in the system.

In fact, you would be better able to tailor your pressure vs. oil weight requirements with that hole present because to change or alter pressure, you now have two options:
- Shimming or cutting the piston spring as necessary, or installing a different one (JNZ unit for example)
- Threading/countersinking the FFOFH's relief hole for something like nitrous jets or similar orifices.

 

[keltalon]

This makes sense.

However, the gasketing system/ mating surface of the ffofh sends the oil coming from said hole to the bore in the gasket where oil would flow when the piston opened.

This logical explanation with a diagram makes sense why closing a relief hole effects idle head oil pressure, however it seems like a substantial.

It doesn't change that this is measured with pink unicorns on stock gauge.

No the hole bleeds directly back into the oil pan. Ask me how I know I put a drill on my oil pump with the oil pan off and watched it just leak on the floor and this is what lead me to look further as to where in the heck is this oil is coming from lo and be hold I discovered the hole!

This makes sense.

However, the gasketing system/ mating surface of the ffofh sends the oil coming from said hole to the bore in the gasket where oil would flow when the piston opened.

This logical explanation with a diagram makes sense why closing a relief hole effects idle head oil pressure, however it seems like a substantial.

It doesn't change that this is measured with pink unicorns on stock gauge.

The hole is before the spring.

 

[LandSpeed-DSM]

The hole is before the spring.

The relief hole and the piston can be treated as one variable geometry hole.

 

[keltalon]

The relief hole and the piston can be treated as one variable geometry hole.

Being before the hole it takes more pressure to push the piston open. The gasket is not milled for the hole which is cost effective for mitsubishi and less confusing when getting a replacement part.

 

[LandSpeed-DSM]

Being before the hole it takes more pressure to push the piston open. The gasket is not milled for the hole which is cost effective for mitsubishi and less confusing when getting a replacement part.

Well, no it doesn't take comparatively more pressure to move the piston if the spring rate is the same.

It takes more flow from the pump to create the equivalent pressure of the hole being closed at the same pump speed.. this is why you would see a system pressure increase.

Pascal's law applies here. This is a basic principal of transmission of fluid pressure in fluid mechanics. It's not a fully confined hydraulic situation, but it works well enough for conversation.

This is why the spring loaded piston and fixed relief hole should be treated as a single hole of variable cross-section for the sake of discussion.. as flow increases, the area of the hole increases to regulate pressure via the k-rate of the spring vs. the initial Force/Area generated at the pump.

To take a simple look at this, pick a specific pump speed/flow.. and change the cross-section allowing oil to return to the pan. The force and area are changing here not the pressure. Unless you have also changed the spring rate in some way.

P = F1/A1 = F2/A2

 

[SaulHudson]

No the hole bleeds directly back into the oil pan. Ask me how I know I put a drill on my oil pump with the oil pan off and watched it just leak on the floor and this is what lead me to look further as to where in the heck is this oil is coming from lo and be hold I discovered the hole!

Exactly what I said, it follows the same path oil would take if it pushed the piston open, back to the pan. So this hole which is around 1/32 would take more than idle oil pressure to make as much difference as you are describing.

How much oil do you think can flow through a 1/32" hole at 15psi?

 

[keltalon]

Well, no it doesn't take comparatively more pressure to move the piston if the spring rate is the same.



P = F1/A1 = F2/A2

LandSpeed-DSM the oil bleeds off before the piston. The hole is where the oil enters and before it reaches the piston. It is not on the exit end but the entrance.

 

[LandSpeed-DSM]

LandSpeed-DSM the oil bleeds off before the piston. The hole is where the oil enters and before it reaches the piston. It is not on the exit end but the entrance.

I'm keen on that. Please re-read what I posted last.

It may not be intuitive, but it's true. Within the environment of the filter housing, at a given operating speed and relief cross-section, pressure in the galley on the discharge side of the pump will be near uniform before leaving to peripherals or the sump via the relief(s).

Whether the fixed relief hole is before or after the spring piston relief hole is inconsequential as far as the fluid pressure is concerned in steady state operation.

 

[keltalon]

I'm keen on that. Please re-read what I posted last.

It may not be intuitive, but it's true. Within the environment of the filter housing, pressure in the galley on the positive pressure side of the pump will be near uniform before leaving to peripherals or the sump via the relief(s).

Okay. My wording should have been it takes more volume of oil to move the spring which doesn't happens at idle:sly:

 

[LandSpeed-DSM]

I've had some clumsy phrasing myself, hence a few ninja-edits..

 

[keltalon]

I've had some clumsy phrasing myself, hence a few ninja-edits..

Sometimes I get caught up. Lol

Exactly what I said, it follows the same path oil would take if it pushed the piston open, back to the pan. So this hole which is around 1/32 would take more than idle oil pressure to make as much difference as you are describing.

How much oil do you think can flow through a 1/32" hole at 15psi?

Trust me a not in terms of trying to reach a desired pressure. when I discovered oil coming out of the hole on the forward facing filter I was curious to see if oil would fall on the floor with the 1g oil filter housing. So I put it back on the engine and at the same drill speed no oil fell on the floor but I did notice more oil coming out of the lifters on the head at (low drill speed) and I could feel the drill drag a little more at the same drill speed which means more oil volume leading to pressure being reached quicker. I had to put the drill on high speed to get it to move enough oil volume to get the same oil stream to come out of the lifters with the forward facing housing than with the 1g oil filter housing. I only whished I had video taped the whole experiment. Like was stated in my earlier posts it took me several days of frustration to find this out I didn't give up because I knew I was on to something.

 

[Sp1kE]

I will do comparisons this spring for everyone.
I am super curious to see the difference.

 

[ceedawg]

Trust me a not in terms of trying to reach a desired pressure. when I discovered oil coming out of the hole on the forward facing filter I was curious to see if oil would fall on the floor with the 1g oil filter housing. So I put it back on the engine and at the same drill speed no oil fell on the floor but I did notice more oil coming out of the lifters on the head at (low drill speed) and I could feel the drill drag a little more at the same drill speed which means more oil volume leading to pressure being reached quicker. I had to put the drill on high speed to get it to move enough oil volume to get the same oil stream to come out of the lifters with the forward facing housing than with the 1g oil filter housing. I only whished I had video taped the whole experiment. Like was stated in my earlier posts it took me several days of frustration to find this out I didn't give up because I knew I was on to something.

Interesting and the vid would have definitely spoke volumes to convince the skeptics. Glad mines is welded thanks again Kels.

 

[keltalon]

Interesting and the vid would have definitely spoke volumes to convince the skeptics. Glad mines is welded thanks again Kels.

Your engine is more glad! Lol

 

[SaulHudson]

Interesting and the vid would have definitely spoke volumes to convince the skeptics. Glad mines is welded thanks again Kels.

Did you use a value reading oil pressure gauge to know you had low oil pressure in the first place?

 

[boost97gst]

After looking at the videos again i gotta say, and i know this was brought up and beat to death but without an accurate gauge it is, well, odd. That tiny little hole could cause such a noticeable drop in pressure. Im not completely doubting the mod or the claim, it could help others out, but even with the thinnest oil possible on the hottest day i just wonder how much oil could be getting through that hole to create the significant drop in pressure you saw. But, i will certainly keep this in mind if i ever have to go ffofh.
Just glad it worked for you and you are satisfied with the results. I would just love to see a before/after reading with a good mechanical gauge hooked up.

 

[bryanwheat]

After looking at the videos again i gotta say, and i know this was brought up and beat to death but without an accurate gauge it is, well, odd. That tiny little hole could cause such a noticeable drop in pressure. Im not completely doubting the mod or the claim, it could help others out, but even with the thinnest oil possible on the hottest day i just wonder how much oil could be getting through that hole to create the significant drop in pressure you saw. But, i will certainly keep this in mind if i ever have to go ffofh.
Just glad it worked for you and you are satisfied with the results. I would just love to see a before/after reading with a good mechanical gauge hooked up.

You should check out the oil bleed holes in the cylinder head. With the valve cover off they will spray oil ten feet in the air pretty easily with a nice size stream. These holes are smaller than the hole being talked about here. These are what keeps the oil pressure in the head lower than in the block.