High Flow Oil Filter

[Gary Allan]

I'll finish the analysis here:

The answer would be 100psi applied 50psi across the engine. We can see this "division" since we have no bypass valve to attenuate the restriction presented to flow by the filter.


Now, when in bypass, we have no true indication of how much flow is being relieved. If the port is big enough ..or the pump output low enough, we'll just sit there against the relief with the full knowledge that out of "whatever can fit through the engine" (at that momement..at that visc...etc..etc) that whatever % the bypass valve rating is in relation to the max applied pressure is the maximum (normally, there are always exceptions) loss of potential flow to the engine.

So, if @ 100psi applied pressure, we're @ 10psid (but below the bypass cracking pressure) ..10% of the potential flow is not reaching the engine. It's forced elsewhere (the relief) by the resistance/restriction of the filter.

Over the full range of pre-bypass PSID we can determine how much of the total pump output is going to the engine, merely by reading the below filter reading ..and the applied pressure.

(now read carefully before objecting).

 

[ZeeOSix]

Originally Posted By: Gary Allan

Quote:
confused ... define "realized pump output". If you mean the oil pressure after the filter, then yes that would be the delta P across the filter. So what was your filter delta P measured value when your oil pump was putting out 82 psi in relief mode?


In relief a % of flow "fits" in the engine. This % of flow will equal that % of pressure.

Simply stated. IF 1gpm=100psi of pressure (use a figure that's convenient for the demonstration -whatever visc ..whatever this that or the other thing as long as it works in your head) then .5gpm would develop 50psi.

Can you agree to that? Now first it helps if you want to see what I'm saying.

I may not be communicating it well.

Take these points in isolation. We should be able to integrate them at the end.


I don't think the flow volume (gpm) vs. pressure relationship is very linear, but for this discussion let's assume it is.

Originally Posted By: Gary Allan
That's why a bypass valve is there. To prevent the filter from showing its TRUE resistance/restriction to flow and starving the engine of oil. Now there are higher bypass rated valves on some engines, but that's factored by the OEM (VW/AUDI/etc) ..but your typical filter can develop NO MORE than 15+/- PSID to inhibit flow to the engine.


Yes, the bypass valve is there to prevent the filter from starving the engine IF it becomes overly clogged. It is also there to protect the filter media from blowing out if the psid becomes too great. If it never becomes very dirty, the psid will remain low throughout it's life ... near the same psid it had when brand new. That brand new psid is what I consider the baseline psid for any filter, as debris loading varies in every car and usage. Yes, if a filter has a 15 psi bypass valve, then it should not have a psid higher than 15 when in bypass (if the bypass valve can flow all the oil that needs to be bypassed).

Originally Posted By: Gary Allan
Try this on for size and see if you can agree with this scenario as stated. Don't worry about how we got there ..don't worry about this or that, just see if you can understand me for this example IN ISOLATION ..it doesn't have to have ANY practical application ..it's just for conceptual view.

We have a super duper filter ..titanium can...rebar reinforced media that's a titanium wire mesh.

We have our 100psi relief level pump.

Now ..in whatever manner possible ..whatever visc required ..whatever flow rate ...(doesn't matter)

What are your readings across the filter when 50% of the pump output is being relieved? Now you first have to accept the given that 50% of the pump output is NOT going to the engine and 50% of the pump output IS.


Assuming the pump is in relief at 100 psi, it's not going to be a 50 psid across the filter because again the filter is not as restrictive as an engine's oiling system. The pressure drop from the pump's 100 psi supply to 0 psi (atmospheric pressure in the sump) must be dropped across every flow component starting from the inlet of the oil filter to the sump. Consider the oil filter as component #1 and the entire engine as component #2.

The answer also depends on what the actual flow volume (gpm) is going through the filter & engine with the pump at 100 psi. If the engine is super restrictive, there might only be 3 gpm going through the filter, which means the filter psid will be pretty low. If there is 12 gpm going through the filter because the engine bearings, etc are super loose and not very flow restrictive then the filter will have around a 5 or 6 psid.

There is not enough information in your example to determine any real answer - I threw in some numbers to show why. If you could say that 10 gpm is going through the filter & engine at 100 psi pump pressure, then it might have a solution.

Originally Posted By: Gary Allan

What would gauges look like above and below the filter. The filter has NO BYPASS and was designed to withstand 50000PSID.

What do you get?


It depends on how much gpm volume is going through the filter and engine. The gpm flow going through the filter and engine is determined on their flow resistance and the pump's supply pressure - and of course if the pump can "keep up" with the flow demand at its pressure relief pressure.

Knowing the flow resistance ratio between filter and engine can give you an indication on how the pressure readings will be. Assuming the pump is in relief at 100 psi.

If the engine is 15 times more restrictive than the filter, the filter would have a 6.7 psid. The pressure above the filter would be 100 psi, and 93.3 psi after the filter (engine oil pressure).

If the engine is 30 times more restrictive than the filter, the filter would have a 3.3 psid. The pressure above the filter would be 100 psi, and 96.7 psi after the filter (engine oil pressure).

 

[ZeeOSix]

Originally Posted By: Gary Allan
I'll finish the analysis here:

The answer would be 100psi applied 50psi across the engine. We can see this "division" since we have no bypass valve to attenuate the restriction presented to flow by the filter.


It's not as simple as splitting the psi drops equally. It depends on what the restriction to flow ratio is between the filter and the engine. The only time this would true - a 50/50 split in pressure drop between filter and engine - is IF the filter had the same exact flow resistance as an entire engine. Nobody makes a filter that restrictive!

 

[Gary Allan]

Quote:
Assuming the pump is in relief at 100 psi, it's not going to be a 50 psid across the filter because again the filter is not as restrictive as an engine's oiling system.


Ah-ah-ah

..you broke the rules... naughty

That's when it's a single flow. It's no longer a flow dictated series circuit as viewed by the pump/filter/engine. It's viewed as a filter vs. a relief port that both see 100psi ..the engine will merely produce whatever pressure the flow it sees can produce.

When the pump is out of relief, then the filter MUST fall in a subordinate position to the engine since the pressure "developed" across all resistances and restrictions will fall in proportion (*). In THAT scenario the filter MUST be very small ..because the engine is VERY BIG.

In relief it doesn't matter one way or the other ..big engine ..small engine...the "divergent" flow merely applies 100psi and what will fit ..will fit..and what won't ..goes to the relief.

The filter NEED NOT fall into proportion since it's NO LONGER A FLOW DICTATED CIRCUIT ..but a "pressure over resistance" circuit.

 

[ZeeOSix]

Originally Posted By: Gary Allan
Quote:
Assuming the pump is in relief at 100 psi, it's not going to be a 50 psid across the filter because again the filter is not as restrictive as an engine's oiling system.


Ah-ah-ah

..you broke the rules... naughty

That's when it's a single flow. It's no longer a flow dictated series circuit as viewed by the pump/filter/engine. It's viewed as a filter vs. a relief port that both see 100psi ..the engine will merely produce whatever pressure the flow it sees can produce.


Not so fast ...

When the oil pump puts 100 psi on the inlet of the filter, the flow volume that goes down the filter & engine will be X gpm depending on the total flow restrictiveness of that circuit. Any oil volume that does not go into the filter & engine goes back to the pump inlet or sump. I think we can both agree on that fact, right?

Originally Posted By: Gary Allan
When the pump is out of relief, then the filter MUST fall in a subordinate position to the engine since the pressure "developed" across all resistances and restrictions will fall in proportion (*). In THAT scenario the filter MUST be very small ..because the engine is VERY BIG.


When the oil pump is out of relief, there is actually LESS oil volume going through the filter and engine because the pressure level is lower based on the characteristics of a positive displacement pump. When the oil pump is putting the relief pressure on the system is when the flow is always highest. This means the filter psid is at it's highest point, and also the engine's oil pressure is at it's highers point. The filter is always "very small" compared to the engine. That is why it's flow resistance is typically 15 times less than an engine. A filter flows very well compared to an engine.

Originally Posted By: Gary Allan
In relief it doesn't matter one way or the other ..big engine ..small engine...the "divergent" flow merely applies 100psi and what will fit ..will fit..and what won't ..goes to the relief.


Yes, that's true ... basically what I said above. When the oil pump is in relief - meaning it's putting out its MAX pressure - whatever flow will go down the filter & engine at 100 psi will be the flow. But again, the pressure drop across the filter and the pressure drop across the engine still depends on the flow resistance ratio between the two. If the engine is 15 times more resistive than the filter than there will be 1/15 the supply pressure dropped across the filter and 14/15 the supply pressure dropped across the engine. That's how fluid flow works ... it has to be that way.

Originally Posted By: Gary Allan
The filter NEED NOT fall into proportion since it's NO LONGER A FLOW DICTATED CIRCUIT ..but a "pressure over resistance" circuit.

... lost ya there. Any time there is the same flow volume going through the filter as there is going through the engine, there must be a pressure drop across the filter and across the engine. The pressure drop across each one will be determined by their specific flow resistance. And the sum of their pressure drops will equal the supply pressure ... always, regardless if the oil pump is in pressure relief or not. This holds true at any engine RPM, any oil viscosity.

 

[Gary Allan]

Quote:
When the oil pump puts 100 psi on the inlet of the filter, the flow volume that goes down the filter & engine will be X gpm depending on the total flow restrictiveness of that circuit.


Absolutely! What you're arguing about is how you don't see the filter altering its apparent resistance (in a flow dictated non-relieved flow ie flow through a resistance = a pressure) to its TRUE resistance when it's in a pressure over restriction non-flow dictated circuit.

Again, without a bypass, the PSID across the filter would be up to 100% of the applied pressure if 100% of the flow went out the relief (assume a transient if that's what allows you to make it work - assume a totally empty engine beyond the filter ..and an extremely tight media ..of whatever micron level you need to allow that to work ...and again, it's like how many psychiatrists it takes to change a light bulb - only one, but the light bulb has to want to change ..you actually have to decide to see what I'm communicating ..and not predisposed to disprove it ..otherwise ..we can keep spinning this around for about 100 more posts

)

So, imagine flow going from zero to 100gpm ..and empty engine behind the media ..and 100psi limits on the pump...until that engine envelopes enough to produce "back pressure" ..that filter will appear EXTREMELY resistant to flow ..TREMENDOUS pressure across it....

..because that's how it is, it cannot easily pass fluid.

Now when you have the INCREDIBLE restriction of the engine providing BACK PRESSURE ..shoring up the back side of the media ..then all that TREMENDOUS RESISTANCE ..just evaporates into next to nothing.

..but for us mundanes ..we have a bypass valve ..making the TREMENDOUS INHERENT RESISTIVE NATURE of the common filter ..easily manageable for out engines ..so that we don't have to worry about it.

 

[Gary Allan]

Let me add a qualifier here

Quote:
making the TREMENDOUS INHERENT RESISTIVE NATURE


..as defined by potential pressure developed across it.

 

[ZeeOSix]

Originally Posted By: Gary Allan
Quote:
When the oil pump puts 100 psi on the inlet of the filter, the flow volume that goes down the filter & engine will be X gpm depending on the total flow restrictiveness of that circuit.


Absolutely! What you're arguing about is how you don't see the filter altering its apparent resistance (in a flow dictated non-relieved flow ie flow through a resistance = a pressure) to its TRUE resistance when it's in a pressure over restriction non-flow dictated circuit.


So where's the disconnect? You need to more clearly define you're terminology. "in a pressure over restriction non-flow dictated circuit" ... what's the real meaning of that phrase?

If you are eluding to the fact that when the oil pump is out of relief that ALL the oil volume coming out of the pump goes through the filter & engine, then yes that is no surprise. But the fact is even when the pump is out of relief there is still a psid across the filter if there is flow through it. You may not realize it by looking at an oil pressure gauge after the filter because the filter's restiveness is invisible when the pump is out of relief (unless you have a filter psid gauge to monitor).

What's happening when the pump is not in relief is that the oil pump is running closer to its pressure relief point with a more restrictive oil filter vs. not.

Originally Posted By: Gary Allan
Again, without a bypass, the PSID across the filter would be up to 100% of the applied pressure if 100% of the flow went out the relief (assume a transient if that's what allows you to make it work - assume a totally empty engine beyond the filter ..and an extremely tight media ..of whatever micron level you need to allow that to work ...and again, it's like how many psychiatrists it takes to change a light bulb - only one, but the light bulb has to want to change ..you actually have to decide to see what I'm communicating ..and not predisposed to disprove it ..otherwise ..we can keep spinning this around for about 100 more posts

)

So, imagine flow going from zero to 100gpm ..and empty engine behind the media ..and 100psi limits on the pump...until that engine envelopes enough to produce "back pressure" ..that filter will appear EXTREMELY resistant to flow ..TREMENDOUS pressure across it....

..because that's how it is, it cannot easily pass fluid.


I can't agree with you here. The filter is the same resistance to flow regardless if there is back pressure on it or not. The psid across the media is a measure of it's resistance to flow, and the psid will be the same if say 10 gpm is flowed through it with or without back pressure.

If the engine was void of all oil in it's passages, etc the oil pump would not build up to 100 psi until the entire engine was enveloped in oil flow. The oil pump would put out whatever gpm it does at say 800 RPM engine speed upon start-up. This is exactly what happens when you install a new bone dry oil filter during and oil change and start the engine for the first time. The filter gets an in rush of X gpm of oil based on the speed of the engine at start-up. The oil pump probably only builds a few psi until the engine circuits are filled with oil ... then the oil pressure rises quickly. Anyone with an oil pressure gauge can see this happening. You do notice that it takes some time to build oil pressure after an oil change ... this is why, it takes a few seconds to fill the engine circuits.

If the oil filter saw an instantaneous 100 psi at start-up, every filter in the world would be blown to smithereens. It would also take a super high volume of oil (100+ gpm, 200 gpm?) to make the pump build to 100 psi with only a free flowing oil filter trying to block the flow.

Originally Posted By: Gary Allan
Now when you have the INCREDIBLE restriction of the engine providing BACK PRESSURE ..shoring up the back side of the media ..then all that TREMENDOUS RESISTANCE ..just evaporates into next to nothing.


Like I said above, once the engine passages etc are filled with oil then the oil pressure builds up. If the pump never went into pressure bypass, then the oil flow volume hasn't changed and the psid across the filter hasn't changed. All that changes was the engine resistance became apparent to the oil pump and the pump's pressure increased accordingly to get the same oil volume through the filter & engine series circuit. Agree with that?

Originally Posted By: Gary Allan
..but for us mundanes ..we have a bypass valve ..making the TREMENDOUS INHERENT RESISTIVE NATURE of the common filter ..easily manageable for out engines ..so that we don't have to worry about it.

The filter's bypass valve has nothing to do with the restrictiveness to flow of the filter's media. The bypass valve will only open IF the psid is higher than the valve's opening psi.

If the filter's bypass valve never opened then it would have no factor in the psid seen across the filter.

After all this discussion, I've come to realize that the filter bypass valve should never open when a cold start is done on a bone dry filter (after an oil change). The reason I say that is because at start-up the engine RPM is low and the oil volume that initially hits the dry filter is low. The only way the filter's bypass could open is if the oil pump produced a head pressure above the bypass setting, and it can't do that because it's only taking a few psi from the pump (well below the bypass setting) to push the initial in-rush of oil through the dry filter.

Now if you did a dry start with oil at -20 deg F, then maybe the bypass valve would open.

 

[Gary Allan]

Okay ..we're getting close to "game playing" time.

I'll spell out things as givens that you can ignore over and over again (not concede to) and continue to place objections to the things you can manage ..but the exchange barometer is tilting in the wrong direction for getting somewhere

Quote:
what's the real meaning of that phrase?


I'll state it for the 14th time (no- I didn't count)


When out of relief, the FLOW trough the restrictions DICTATES the pressure. Easy enough to see. The oil has "no choice" but to pass through every hole, twist, orifice, rough conduits ..smoothed conduits, skinny ..fat ..long ..short.

I'm sure you understand that. You appear to be a rather smart man. No need to Romper Room this for you

In a pressure over resistance circuit ..the pressure through the resistance determines the flow.

Surely a man of your keen grasp can see the simple, but distinct differences of the two models.

A YES or NO will work.

We'll do this in small steps here.

Some paradigms are hard to let go of ..but I'm here to help you out of that prison!

 

[Gary Allan]

Quote:
What's happening when the pump is not in relief is that the oil pump is running closer to its pressure relief point with a more restrictive oil filter vs. not.



What's it matter? Either filter is capable of passing the flow requirements of the engine at most sensible volumes to develop no APPRECIABLE PSID. How much less than
More restrictive or less restrictive ..neither make any difference of merit in use in or out of relief. Both will fall into the narrow range of "next to nothing" and the bypass threshold.

 

[Gary Allan]

Quote:
The filter is the same resistance to flow regardless if there is back pressure on it or not.


..ah-ah-ah

you broke the rules again ..naughty naughty

ring ring ..

..as defined by the POTENTIAL pressure developed across it

Any and all spec'd filters (probably) have EXCESS capability to pass 100% of all potential oil flow.

That's obvious and it should be obvious to you that (at this point) that we should have to piddle around with common sense points. I had hoped were were dwelling in adult land (that barometer is tiling even more into Playland

)

Think of time constants and inductors ..and ELI the ICEman

 

[ZeeOSix]

Originally Posted By: Gary Allan
Okay ..we're getting close to "game playing" time.

I'll spell out things as givens that you can ignore over and over again (not concede to) and continue to place objections to the things you can manage ..but the exchange barometer is tilting in the wrong direction for getting somewhere

Quote:
what's the real meaning of that phrase?


I'll state it for the 14th time (no- I didn't count)

When out of relief, the FLOW trough the restrictions DICTATES the pressure. Easy enough to see. The oil has "no choice" but to pass through every hole, twist, orifice, rough conduits ..smoothed conduits, skinny ..fat ..long ..short.

In a pressure over resistance circuit ..the pressure through the resistance determines the flow.

A YES or NO will work.

We'll do this in small steps here.

Some paradigms are hard to let go of ..but I'm here to help you out of that prison!

Yeah, no reason to go "romper room" ... so please just correspond without the antics.

Even when the pump is IN relief, "the FLOW trough the restrictions DICTATES the pressure." The flow vs pressure relationship doesn't care if the oil pump is in relief or not. The only thing that happens when the oil pump is in pressure relief is that the pressure put on the filter & engine system is limited to a maximum value. At that MAX pump pressure you obtain the MAX flow possible through the filter & engine ... and "the pressure through the resistance determines the flow."

So YES ... we agree on this point and I have said this about 12 different ways so far (the red text are your exact words). Off to your next post.

 

[ZeeOSix]

Originally Posted By: Gary Allan
Quote:
What's happening when the pump is not in relief is that the oil pump is running closer to its pressure relief point with a more restrictive oil filter vs. not.


What's it matter? Either filter is capable of passing the flow requirements of the engine at most sensible volumes to develop no APPRECIABLE PSID. How much less than span>


This is what confuses the issue so much in this discussion. In one post you claim oil filters are "extremely resistant to flow", but here you talk like they are barely restrictive (red text). Which way is it? They are either restrictive or not restrictive. Their flow resistance doesn't magically change. As I've said from the beginning, oil filters are very free flowing compared to the engine circuit. That's why the oil filter is 15 times (or more) less restrictive than an engine.

Originally Posted By: Gary Allan
More restrictive or less restrictive ..neither make any difference of merit in use in or out of relief. Both will fall into the narrow range of "next to nothing" and the bypass threshold.


The point I was tying to get across (if you go back and re-read that original post) is that when the pump is out of relief you can not tell how restrictive an oil filter is because ALL the oil coming out of the pump must go through the filter. BUT, if you put a delta P gauge across the more restrictive filter you would see a higher psid and the oil pump would be running at a higher output pressure. What most people don't realize is that a more restrictive filter will make the oil pump run closer to it's pressure relief setting. But yes, as long as the pump is not put into relief way too soon, then the oil flow to the engine should be adequate.

 

[ZeeOSix]

Originally Posted By: Gary Allan
Quote:
The filter is the same resistance to flow regardless if there is back pressure on it or not.


..ah-ah-ah

you broke the rules again ..naughty naughty

ring ring ..

..as defined by the POTENTIAL pressure developed across it

I think this is where your disconnect stems from. If you don't agree that an oil filter (with fixed flow resistance) doesn't have the same psid with the same oil flow and viscosity through it regardless if there is back pressure on it or not, then you're missing a key component to the understanding of what's happening.

If I put an oil filter on a bench and flow 10 gpm of 200 deg F 5w-30 oil through it with 3 psi of "back pressure" on the filter, it will produce 5 psid. The pump supply pressure to push the 10 gpm through the filter will only be 8 psi.

If I put an oil filter on an engine and flow 10 gpm of 200 deg F 5w-30 oil through it with 70 psi of "back pressure" on the filter, it will produce 5 psid. The pump supply pressure to push the 10 gpm through the filter and engine will be 75 psi due to the added resistance of the engine in the circuit.

Please read that a few times and try to visualize what's going on in the oiling system. This is why it doesn't matter if there is the entire back pressure on the filter from the engine or not ... what only matters is the volume (gpm) and viscosity going through the filter which causes the psid. And it doesn't matter what oil pump pressure was required to achieve the 10 gpm, as long as 10 gpm of flow was obtained.

If you can't see that, then you are missing a key factor in understanding that what happens in the filter & engine series circuit doesn't matter if the pump is in relief or not, or if there is total back pressure on the filter or not. The only things that really matter is what the resistance ratio is between the filter and engine (1:15 for example) and what the maximum pump supply pressure can be based on it's relief valve setting. Those factors alone will dictate how much oil flow goes down the filter & engine series circuit at each engine RPM and oil viscosity point.

Originally Posted By: Gary Allan
Any and all spec'd filters (probably) have EXCESS capability to pass 100% of all potential oil flow.


So why have you previously claimed that oil filters are "extremely resistive to flow" if they can easily pass 12 or 15 gpm? Changing your position only confuses the whole discussion.

Yes or No ... do you think oil filters are "extremely resistive to flow" compared to an engine oiling system?

Originally Posted By: Gary Allan
That's obvious and it should be obvious to you that (at this point) that we should have to piddle around with common sense points. I had hoped were were dwelling in adult land (that barometer is tiling even more into Playland

)


I think we have to divert and "piddle around" to some degree because the communication and terminology factor is dragging it down.

My suggestion is to end this discussion at this point and you can go chew on some of this stuff ... let it soak in awhile, maybe re-read some of the posts. All of a sudden the light bulb will probably go off. It's been fun!

 

[Gary Allan]

Quote:
The flow vs pressure relationship doesn't care if the oil pump is in relief or not.


Ah...but the distinction, which you could have simply conceded to, is that in relief, you have an attenuated pressure ..and the flow can be whatever the restrictions allow.

Out of relief ..FLOW is the irresistable KING in the equation balancing act of mathematics.

See where I'm getting the game playing notions? You're avoiding agreement in things like this and playing word antics yourself

This never had to be a "contest" ..but let's go around and around and around and around some more.

 

[Gary Allan]

..and while we're at a pause here..

Quote:
I think this is where your disconnect stems from. If you don't agree that an oil filter (with fixed flow resistance) doesn't have the same psid with the same oil flow and viscosity through it regardless if there is back pressure on it or not, then you're missing a key component to the understanding of what's happening.


I'll show you your major disconnect in potential scenarios that you obviously cannot conceive. This should be your missing key to understanding what's going on..

I am here to help

So, in the below scenario ..with visual aids ..can you see how a filter's resistance ..IN TERMS OF POTENTIAL PSID can change ..even at the same flow rate?

It's a pretty simple example.

 

[ZeeOSix]

Originally Posted By: Gary Allan

See where I'm getting the game playing notions? You're avoiding agreement in things like this and playing word antics yourself

This never had to be a "contest" ..but let's go around and around and around and around some more.


The game playing is all in your head. You either want to discuss this and get somewhere or you just want me to agree with your false viewpoints. Sorry, can't make agreements to false information.

If you want to continue this discussion I suggest you get serious about it and stop playing antics.

If I feel like it later, I might respond to your last couple of posts. I also have a feeling you do not even try to understand the things I'm relaying because you're insight is too burned into your brain to allow any new insight.

 

[Gary Allan]

Thank you very much!

 

[ZeeOSix]

Originally Posted By: Gary Allan

I'll show you your major disconnect in potential scenarios that you obviously cannot conceive. This should be your missing key to understanding what's going on..

I am here to help

So, in the below scenario ..with visual aids ..can you see how a filter's resistance ..IN TERMS OF POTENTIAL PSID can change ..even at the same flow rate?

It's a pretty simple example.


If the oil flow rate and viscosity in both sketches you show above is exactly the same, then the psid across the filter has to be exactly the same in both sketches. If you can't understand this then you will always be mis-guided in your thinking on what's really going on.

Seriously ... Please explain to me how the filter's psid in the top sketch can be higher than the filter's psid in the lower sketch if the oil flow rate and viscosity is the same in both sketches. If the oil flow and viscosity is NOT the same in both sketches, then elaborate and tell me why.

 

[Gary Allan]

Soopy?