Hengst oil filter inflow holes changed, should I use this new filter??

[Actros617]

So a bit of a back ground, this oil filter is been used in a 2006 Land Rover LR3 with 4.0 V6 SOHC, same 4.0 V6 SOHC engine used in a 1999-2010 Ford Explorer, Ranger, ect. I've been switching back and forth oil filters between Hengst H10W18 and Mahle OC705 and they're very identical to each other in shape form and including the inlet holes.

When I reordered Hengst this time around the top inlet holes holes are 2 less and smaller then what it used to be! But still has the approved use for LR3, and even for a 2012-2018 RAM 1500 with 5.7L

The old Hengst that I last used looked like this (PIC BELOW)! it has 8 inflow holes just like mahle. And R.A. has this photo on their site when ordering.

I've read a few threads regarding oil filter Inlet holes that may or may not impact on flow, however given this circumstances which filter is quite diffrent then it used to be, what are your thought, use or not to use?


PS Interesting observation old Hangst used to be made in Germany and now its moved to Ukraine, quality and construction is still the same as old, except the new one has a slight overspray on the edge, and its in gloss Black vs matte black

PS

 

[slacktide_bitog]

Use it. If you don't use it, cut it open

 

[Sandstorm]

It shouldn't be an issue

 

[dnewton3]

There's plenty of area in the inlet holes to flow the proper amount of fluid.
Use it.

 

[RyanY]

The "artistic" hole arrangement will have no effect on flow. Made in Ukraine is also fine unless Putin actually conquers them. In that case we should avoid them at all costs.

 

[ZeeOSix]

The filter with a little less flow area in the base plate inlet holes might produce 1-2 PSI more dP at high RPM oil flow, but that will not matter to the positive displacement oil pump. One goal of filter engineers is to ensure the dP across all elements of the filter (base plate, media and center tube) is within reason and will work for all vehicles they specify it for. This has been hashed out 100s of times over the years in this forum.

 

[ZeeOSix]

I've read a few threads regarding oil filter Inlet holes that may or may not impact on flow ...

Do some study on positive displacement oil pumps used in engine oiling systems. The only time any oil flow is reduced in the oiling system is when the PD oil pump is in pressure relief, which is a pretty hard condition to achieve unless you rev the engine real high with cold thick oil. When the oil is at full operating temperature, it's really hard to get the oil pump to go into pressure relief, even near or at engine redline.

 

[CR94]

In other words, it's irrelevant---although much-discussed.

 

[ZeeOSix]

Or in other, other words ... PD oil pumps and engine oiling systems don't work like the water system in a house, and are therefore misunderstood by a lot of people. That's why when they look at a base plate or at a center tube and it doesn't look super "wide open" they think that oil flow to the engine is being "choked down" and reduced. But it's not because of the PD oil pump. Only time the flow can be reduced is if the pump hits pressure relief, which is a pretty rare occurrence. A lot of people also don't have a good feeling for the correlation between the flow area and what the resulting "dP vs flow curve" would look. It's not really intuitive unless you actually plot out the data to see the curve with your eyes. The dP vs flow is much less than most people would guess it to be.

 

[kschachn]

A previous thread with a partial list of all the previous threads:

Hengst H97W05 (7317 size) has few inlet holes

Threw this Hengst filter on an order from Rock Auto. Was hoping it was made in the plant her in South Carolina, but this one is made in Poland. Seems like a nice heavy filter. However it has fewer inlet holes than any other filter this size I have seen. Compared to the OEM Nissan filter -...

bobistheoilguy.com

 

[ZeeOSix]

Calculated dP vs Flow curves for a Fram base plate and center tube using a good dP calculating tool. Done for both cold and hot oil (viscosity noted in the graphs). Most cars on the road are not going to put out any more than 8-10 GPM at redline.

Base plate had 5.7% open area - meaning that the total flow area of the base plate inlet holes were 5.7% of the total surface area of the base plate.

Center tube had 10.7% open area - meaning that the total flow area of the center tube holes were 10.7% of the total surface area of the center tube.

 

[johnmyster]

That's a Ford Truck filter. Six holes, paired. Crazy my brain when straight to that.

 

[johnmyster]

The filter with a little less flow area in the base plate inlet holes might produce 1-2 PSI more dP at high RPM oil flow, but that will not matter to the positive displacement oil pump. One goal of filter engineers is to ensure the dP across all elements of the filter (base plate, media and center tube) is within reason and will work for all vehicles they specify it for. This has been hashed out 100s of times over the years in this forum.

It might come up often because PD pumps do have a relationship between volume flow rate and dP. So when "flow is not impacted by backpressure" gets stated, it's not entirely true and creates some confusion/resistance. We shouldn't say it "will not matter" because it does.

Yes, a PD pump is certainly not a centrifugal pump. A gear or gear-rotor pump will have clearance between the elements. The more dP across the pump, the more backflow (pump slip) across those elements will occur. Viscosity of the fluid will also play into this. Negligable at high RPM? Probably. Negligable at low RPM with hot oil? Maybe, maybe not.

If it doesn't matter, it's not because positive displacement means constant displacement. Rather, it would be because the slip rate for a particular pump at particular viscosity and particular speed is a small/negligible percentage of overall flow. Even so, one would need to do the experiment/math to see at what order of magnitude the difference would be seen.

But I do agree, we aren't very good visual engineers. We tend to see holes, turns, and directional changes and over-estimate the additional dP imparted onto fluid flow past that obstacle, without actually doing the math.

Estimate on my truck's pump is 30 gpm, so that pushes a little further up those filter restriction curves...I'm glad it has a big filter.

 

[dubber09]

Save the filter, it will be a collectible nostalgia item after Ukrainians take their country back from Zelensky's regime; it happened with Germany when WWII ended.

 

[Dave Hess]

Even at redline these holes will flow enough oil.

 

[ZeeOSix]

It might come up often because PD pumps do have a relationship between volume flow rate and dP. So when "flow is not impacted by backpressure" gets stated, it's not entirely true and creates some confusion/resistance. We shouldn't say it "will not matter" because it does.

Yes, a PD pump is certainly not a centrifugal pump. A gear or gear-rotor pump will have clearance between the elements. The more dP across the pump, the more backflow (pump slip) across those elements will occur. Viscosity of the fluid will also play into this. Negligable at high RPM? Probably. Negligable at low RPM with hot oil? Maybe, maybe not.

If it doesn't matter, it's not because positive displacement means constant displacement. Rather, it would be because the slip rate for a particular pump at particular viscosity and particular speed is a small/negligible percentage of overall flow. Even so, one would need to do the experiment/math to see at what order of magnitude the difference would be seen.

But I do agree, we aren't very good visual engineers. We tend to see holes, turns, and directional changes and over-estimate the additional dP imparted onto fluid flow past that obstacle, without actually doing the math.

Of course there is always some PD "slip" going on as you've pointed out. The slip will be more so with thinner oil viscosity and higher RPM. For all practical purposed for BITOG discussions, one should assume the PD pump talk is with a healthy pump with minimal slip. Oil pumps with excessive slip are either designed wrong, or are pretty worn out and not in a healthy mechanical condition.

Here's a good example of flow vs RPM performance measurements of some LS engine oil pumps. The flow vs RPM line is pretty linear up to where the pressure relief kicks in or the pump cavitates, which means the pump slip is pretty minimal. So for all practical purpose in these BITOG PD pump discussions, one can assume a mechanically healthy pump operates similar to this.

Estimate on my truck's pump is 30 gpm, so that pushes a little further up those filter restriction curves...I'm glad it has a big filter.

How are you coming up with 30 GPM for your truck - what engine? Is that pump performance graph for the oil pump in your truck? I wouldn't think so since it's showing low RPM info, unless this is some perhaps some big low RPM diesel engine.

 

[ZeeOSix]

Here's the engine oil pressure vs engine RPM at constant oil temperature that I collected on my Z06. You can see some slight curve roll-over which indicates some pump slip as the oil pressure increases, but it's pretty minimal, indicating a pretty mechanically healthy oil pump.

 

[johnmyster]

The up to 30 gpm figure was a quick google lookup for a duramax pickup, which may or may not be correct. Cycling the sump every 5 seconds seems extreme, but not impossible.

The pump curve presented was also a quick google lookup, non-automotive, relevant in that it shows slip correction curves as well as pressure dependence for a PD pump. Is a few psi difference between a good flowing filter and a restrictive one going to grossly change the volume flow rate of an oil pump? No. Some, yes. Unlike alot of industrial pump situations where the fluid is maintained in a fairly tight temperature window, our engines are not. I acknowledge that some filter restriction is small in the grand scheme of the total circuit but it's still not accurate to say a PD pump will move the same volume of fluid per revolution regardless of pump head.

Pump "slip" is actually more pronounced at low RPM. If pump clearances allow (lets say) 2 gpm of backflow at 15 psi of head, then that 2 gpm is a greater proportion of loss at low speed. That's why you'll see the negative second derivative (concave down) shape on a flow vs speed curve. An isobaric flow curve of flow volume vs speed is a very different animal than that you've presented...pressure vs speed into a given orifice (engine) which is neither isobaric nor iso flow.

These days there are also lots of variable displacement pumps out there. (You know this.) The one on my BMW was spring loaded vs oil pressure. So it still increased pressure with RPM, but not as much as a typical PD pump. (It takes incrementally more force to compress a spring further.)

Does the Z06 have piston cooling jets that are inactive below a certain pressure? That would introduce variable orifice into the graph you've shown.

 

[ZeeOSix]

The up to 30 gpm figure was a quick google lookup for a duramax pickup, which may or may not be correct. Cycling the sump every 5 seconds seems extreme, but not impossible.

I highly doubt it's 30 GPM. Even insane Subaru oil pumps aren't even flowing that much.

The pump curve presented was also a quick google lookup, non-automotive, relevant in that it shows slip correction curves as well as pressure dependence for a PD pump. Is a few psi difference between a good flowing filter and a restrictive one going to grossly change the volume flow rate of an oil pump? No. Some, yes.

The reduction if pump flow vs engine RPM as I showed in my curve above is mainly from pump slip, not from the restriction of the oil filter. A typical oil filter is only 1/15th the flow restriction of an engine's oiling system. So adding few more PSI of dP on the pump outlet really isn't going to be much effect on pump slip.

Unlike alot of industrial pump situations where the fluid is maintained in a fairly tight temperature window, our engines are not. I acknowledge that some filter restriction is small in the grand scheme of the total circuit but it's still not accurate to say a PD pump will move the same volume of fluid per revolution regardless of pump head.

I didn't really say or mean that part in bold. What I basically mean is that the restriction difference between oil filters will not really change the pump output in any meaningful way unless the pump is in pressure relief. See my comment above regarding that the filter is a small portion of the back pressure on the pump's outlet - approx 1/15th of the total dP across the entire oiling system fed by the pump. If you ran no filter vs a filter with 5 PSI of dP at full pump flow (without the pump in relief), the difference in pump volume going to the engine will be minuscule - not really worth mentioning at the level of these oil filter discussions to help keep it simple. It won't really matter enough to worry about, because adding 5 more PSI of dP to the pump outlet isn't going to make any meaningful pump output volume change due to a sliver of added slip caused by just 5 more PSI of back pressure. When comparing two oil filters with different dP vs flow curves, it's probably more like only 2-3 PSI difference of dP to the pump back pressure. No PD oil pump output flow is going to be effected from that unless it's totally worn out.

Pump "slip" is actually more pronounced at low RPM. If pump clearances allow (lets say) 2 gpm of backflow at 15 psi of head, then that 2 gpm is a greater proportion of loss at low speed. That's why you'll see the negative second derivative (concave down) shape on a flow vs speed curve. An isobaric flow curve of flow volume vs speed is a very different animal than that you've presented...pressure vs speed into a given orifice (engine) which is neither isobaric nor iso flow.

The curve I showed of the Z06 oil pressure vs engine RPM was at a constant oil temperature/viscosity. The oil temperature and oil pressure sensors are located right after the oil comes from the pump. The pressure vs RPM curve is pretty linear up until around 3000 RPM then starts falling off after that. So that tells me the pump slip isn't as bad at lower RPM on this particular pump. Pump slip is a much stronger function of pump output pressure, which is a function of pump RPM, and that's why it rolls off at higher RPM. If that same test was done with cold thicker oil, the slip should be less because pump slip is worse with a thinner viscosity (ie, the oil "slips" past the pump clearances easier). The pump would hit pressure relief easier/sooner at a lower RPM of course if the oil is thicker.

These days there are also lots of variable displacement pumps out there. (You know this.) The one on my BMW was spring loaded vs oil pressure. So it still increased pressure with RPM, but not as much as a typical PD pump. (It takes incrementally more force to compress a spring further.)

Does the Z06 have piston cooling jets that are inactive below a certain pressure? That would introduce variable orifice into the graph you've shown.

The Z06 with the LS6 doesn't have piston oil squirters. Ford Coyote V8s do however have piston squirters that are just fixed orifice. Variable displacement oil pumps used in engines are still PD pumps and still have a pressure relief valve. They just don't have a typical pressure vs RPM output curve like shown above because of the wonky control profiles engineers dream up for them to save 0.01 MPG, lol.

 

[johnmyster]

To be clear, I'm calling you on an upfront blanket statement that you made.

The filter with a little less flow area in the base plate inlet holes might produce 1-2 PSI more dP at high RPM oil flow, but that will not matter to the positive displacement oil pump. One goal of filter engineers is to ensure the dP across all elements of the filter (base plate, media and center tube) is within reason and will work for all vehicles they specify it for. This has been hashed out 100s of times over the years in this forum.

Do some study on positive displacement oil pumps used in engine oiling systems. The only time any oil flow is reduced in the oiling system is when the PD oil pump is in pressure relief, which is a pretty hard condition to achieve unless you rev the engine real high with cold thick oil. When the oil is at full operating temperature, it's really hard to get the oil pump to go into pressure relief, even near or at engine redline.

Or in other, other words ... PD oil pumps and engine oiling systems don't work like the water system in a house, and are therefore misunderstood by a lot of people. That's why when they look at a base plate or at a center tube and it doesn't look super "wide open" they think that oil flow to the engine is being "choked down" and reduced. But it's not because of the PD oil pump. Only time the flow can be reduced is if the pump hits pressure relief, which is a pretty rare occurrence. A lot of people also don't have a good feeling for the correlation between the flow area and what the resulting "dP vs flow curve" would look. It's not really intuitive unless you actually plot out the data to see the curve with your eyes. The dP vs flow is much less than most people would guess it to be.

I think we've established, it does matter, even if not an order of magnitude, or twofold, etc. Why not say something like, "it will matter little" or "the difference will be negligable" rather than standing beside a blanket and misleading statement about oft misunderstood PD pumps. Centrifugal pumps and gear pumps doing work on incompressible fluids both have curves that are...curves.

The reduction if pump flow vs engine RPM as I showed in my curve above is mainly from pump slip, not from the restriction of the oil filter.

We have established that pump slip is a function of backpressure, which is additive for all components in the system, including the filter. The pump curve graph I shared shows this. Backpressure and viscosity determine slip. So yes, your curve shows slip increasing as pressure increases, but your data log graph is not one of pump flow vs engine rpm. It is pressure vs rpm, which is a related but different. To call the two the same would be making a big assumption about the fluid dynamic behavior of every oiling passage/component in the engine at various flow/pressure states. I don't remember many linear relationships in fluid dynamics.

The curve I showed of the Z06 oil pressure vs engine RPM was at a constant oil temperature/viscosity. The oil temperature and oil pressure sensors are located right after the oil comes from the pump. The pressure vs RPM curve is pretty linear up until around 3000 RPM then starts falling off after that. So that tells me the pump slip isn't as bad at lower RPM on this particular pump. Pump slip is a much stronger function of pump output pressure, which is a function of pump RPM, and that's why it rolls off at higher RPM. If that same test was done with cold thicker oil, the slip should be less because pump slip is worse with a thinner viscosity (ie, the oil "slips" past the pump clearances easier). The pump would hit pressure relief easier/sooner at a lower RPM of course if the oil is thicker.

You recognized it. Then you tried to further proove your point and got it backwards. Pump slip is present at all RPM. It increases with pressure but becomes smaller relative the pump output at higher flow (RPM.) PD pumps are used across the world at constant RPM but variable output flow and/or pressure.

Again, pump slip is not a function of RPM. It is a function of backpressure. In your experiment, backpressure and RPM are not held independent. Slip increases at higher pressure. RPM was the innocent bystander, a variable your test setup did not allow to be held constant.