Oil pressure difference between to oil filters

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I did compare back-to-back the oil pressure recorded through HPTuners between two "Racing Oil Filters" on my based LS6, same oil (RLI HD Low ash 5W40), oil pressure sensor in its OEM spot, same oil temperature (220*F) and same water temperature (185*F), oil filters filled before installing:

- FRAM Racing Hp20:
Idle is 32 PSI
From 3000 rpm to 7400rpm is from 42PSI to 49PSI

- MOROSO Racing 22462:
Idle is 40PSI
From 3000rpm to 7400rpm is from 52PSI to 62PSI

Which one is better than the other in term of oil flow/lubrication and engine safety?
Christian
 
I did compare back-to-back the oil pressure recorded through HPTuners between two "Racing Oil Filters" on my based LS6, same oil (RLI HD Low ash 5W40), oil pressure sensor in its OEM spot, same oil temperature (220*F) and same water temperature (185*F), oil filters filled before installing:

- FRAM Racing Hp20:
Idle is 32 PSI
From 3000 rpm to 7400rpm is from 42PSI to 49PSI

- MOROSO Racing 22462:
Idle is 40PSI
From 3000rpm to 7400rpm is from 52PSI to 62PSI

Which one is better than the other in term of oil flow/lubrication and engine safety?
Christian
Was the oil also changed along with the filter for the 2nd test run?

I've ran 4 or 5 different filters on my LS6 and never say any change in oil pressure.
 
Where is the sensor and relief valve in relation to the pump and filter? Easy question to answer if you have a schematic (even hand drawn).
The oil pressure sensor is way after the oil filter (up on back of the intake manifold area), and the filter bypass is in the block close to the filter.
 
Where is the sensor and relief valve in relation to the pump and filter? Easy question to answer if you have a schematic (even hand drawn).
62loilflow.jpg
 
I did compare back-to-back the oil pressure recorded through HPTuners between two "Racing Oil Filters" on my based LS6 ...
Did the on-dash digital oil pressure read-out correspond to the HPTuner data?
 
Was the oil also changed along with the filter for the 2nd test run?

I've ran 4 or 5 different filters on my LS6 and never say any change in oil pressure.
Hi ZeeOSix, oil was new with the first test:

- FRAM Racing Hp20:
Idle is 32 PSI
From 3000 rpm to 7400rpm is from 42PSI to 49PSI

And was 42 miles old for the second test:

- MOROSO Racing 22462:
Idle is 40PSI
From 3000rpm to 7400rpm is from 52PSI to 62PSI

And as written in initial post, both filters were filled before install.
Christian
 
Interesting… And I was scoffed at (somewhat) for suggesting a less restrictive filter could increase GALLERY oil pressure on an LS engine! I might have to check out one of those Moroso filters for the 6.0 in the Express. I would think more pressure is a good thing, although even the lower pressure numbers are in acceptable LS range.
 
Interesting… And I was scoffed at (somewhat) for suggesting a less restrictive filter could increase GALLERY oil pressure on an LS engine! I might have to check out one of those Moroso filters for the 6.0 in the Express. I would think more pressure is a good thing, although even the lower pressure numbers are in acceptable LS range.
What's strange is that theoretically the oil filter flow resistance should not matter with a PD oil pump that is not in pressure relief. So I'm surprised the idle oil pressure was so much different. I never saw any oil pressure changes on my LS6 using 5 different oil filters as long as the pump wasn't at pressure relief. I made sure the oil temperature and engine RPM above idle was exactly the same when I did all my testing - that's very important.
 
I will assume the relief valve is BEFORE the filter?
Any idea what the relief setting is?
Any idea what the filter bypass setting is?

If both tests were done with similar viscosity oils and similar temps, then there is really only one explnation with a FIXED (not variable displacement) positive displacement oil pump. If the relief valve, and filter are both BEFORE the pressure sensor, (again if same temp, same viscosity), then only what is downstream from your sensor has any influence on pressure given the same flow. A pump produces flow (NOT pressure), and pressure is created from resistance to flow (travels backwards). That means for the pressure to be that different, the flow rate through the system is different. That means your relief valve is opening, and you are losing flow due to a more restrictive oil filter which means your downstream pressure will be lower for a given engine RPM.
 
YES it did read the same minus the constant 0.2PSI offset from the Z06 dashboard engine oil pressure gauge...
Christian
Have you ever seen the oil pressure jump around or seem flaky? The oil pressure sensors used on the LS engines go out all the time. I had to replace mine when the engine only had about 20K miles on it.
 
Interesting… And I was scoffed at (somewhat) for suggesting a less restrictive filter could increase GALLERY oil pressure on an LS engine! I might have to check out one of those Moroso filters for the 6.0 in the Express. I would think more pressure is a good thing, although even the lower pressure numbers are in acceptable LS range.

What's strange is that theoretically the oil filter flow resistance should not matter with a PD oil pump that is not in pressure relief. So I'm surprised the idle oil pressure was so much different. I never saw any oil pressure changes on my LS6 using 5 different oil filters as long as the pump wasn't at pressure relief. I made sure the oil temperature was the same when I did all my testing - that's very important.
ZeeOSix, I did test 5 or more LS6 type oil filters and never had noticeable differences until I got the Fram HP20 from them to test in vivo and report to them, because those one when I received the 5 FRAM Racing HP20 (for free) were giving my engine higher oil pressure.

The FRAM Racing HP20 that is in the low oil pressure zone is the last one I did bought on line, and that is building less oil pressure than the 5 I received from FRAM.
Christian.
PS: my question still remain "Which one is better than the other in term of oil flow/lubrication and engine safety?"
 
I will assume the relief valve is BEFORE the filter?
Any idea what the relief setting is?
Any idea what the filter bypass setting is?

If both tests were done with similar viscosity oils and similar temps, then there is really only one explnation with a FIXED (not variable displacement) positive displacement oil pump. If the relief valve, and filter are both BEFORE the pressure sensor, (again if same temp, same viscosity), then only what is downstream from your sensor has any influence on pressure given the same flow. A pump produces flow (NOT pressure), and pressure is created from resistance to flow (travels backwards). That means for the pressure to be that different, the flow rate through the system is different. That means your relief valve is opening, and you are losing flow due to a more restrictive oil filter which means your downstream pressure will be lower for a given engine RPM.
I doubt the filter flow resistance is making the oil pump go into pressure relief at idle or low RPM, it would have to be super restrictive to do so - and besides the oil pressure readings taken were way below the pump pressure relief setting which I think is around 80 PSI.

If the flow coming out of the pump is changing that much at that low RPM, then maybe there is something going on with the oil pump, like the pressure relief valve in the pump isn't operating consistently (ie, sticky?).
 
ZeeOSix, I did test 5 or more LS6 type oil filters and never had noticeable differences until I got the Fram HP20 from them to test in vivo and report to them, because those one when I received the 5 FRAM Racing HP20 (for free) were giving my engine higher oil pressure.

The FRAM Racing HP20 that is in the low oil pressure zone is the last one I did bought on line, and that is building less oil pressure than the 5 I received from FRAM.
Christian.
PS: my question still remain "Which one is better than the other in term of oil flow/lubrication and engine safety?"
So you have tested 5 different brand filters? What brands, and how did they all compare to all the others tested?

And you have also tested 6 different Fram HP20 filters, but the last one showed different oil pressure than the other 5 Fram HP20 filters? Trying to follow all this testing.
 
So you have tested 5 different brand filters? What brands, and how did they all compare to all the others tested?

And you have also tested 6 different Fram HP20 filters, but the last one showed different oil pressure than the other 5 Fram HP20 filters? Trying to follow all this testing.
I might not be explicit enough...I will try better.

Fram contacted me to test their Racing Oil Filter HP20, I agreed, they sent me five.
I compare those HP20 to what I was using at this time that was best for my engine in term of building up pressure quickly and feeling the lifters, and VIX XP was my benchmark.

I used the 5 HP20 I did received from FRAM, and I did buy 2 HP20 online, those two were giving my engine the low pressure from the initial post.

Is it more understandable?
 
I doubt the filter flow resistance is making the oil pump go into pressure relief at idle or low RPM, it would have to be super restrictive to do so - and besides the oil pressure readings taken were way below the pump pressure relief setting which I think is around 80 PSI.

If the flow coming out of the pump is changing that much at that low RPM, then maybe there is something going on with the oil pump, like the pressure relief valve in the pump isn't operating consistently (ie, sticky?).

I agree...but the flow has to be going somewhere. Either the relief is opening early, sticking, or the pump is getting leaky (very low volumetric efficiency).
 
Have you ever seen the oil pressure jump around or seem flaky? The oil pressure sensors used on the LS engines go out all the time. I had to replace mine when the engine only had about 20K miles on it.
Hi ZeeOSix,
Oil pressure sensor is not OEM and relocated in a ventilated cooler spot...OEM sensor in OEM location failed 3 time before I decided to go that route:
 

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