most engines put out a flow of 5gpms
K&N oil filter observation
- Thread starter Patman
- Start date
- Status
Patman
Staff member
I can't even change my own air filter on this engine let alone pull the oil pan off!quote:
Originally posted by Chris A:
I don't see how a filter could effect the oil pressure at all. Let's take it to the extremes. If you are running no filter, you will get max flow and therefore max pressure. If you have a clogged filter, the bypass valve will open allowing full flow to the bearings. This is especially true since your pressure is remaining the same as the pump is spinning faster. This tells me that your pump is bypassing oil back into the pan via the pressure relief spring.
What I think you need to do is pull the pan (or is it easier to pull the engine on those LT1 F-body's) and put a sensor on the bypass valve to a light on your dash. That way, you could see when it is in bypass mode and we wouldn't have to speculate about anything. Then we could each send you a filter brand of our choice and a qt of your favorite oil and let the testing begin. So, are you up for it?
Really, lets give him something that's not so much work. He should just go to a remote filter with a pressure tap on the inlet and outlet. As long as the differential pressure is less than the bypass setting of the filter we can assume it's filtering.quote:
Originally posted by Chris A:
I don't see how a filter could effect the oil pressure at all. Let's take it to the extremes. If you are running no filter, you will get max flow and therefore max pressure. If you have a clogged filter, the bypass valve will open allowing full flow to the bearings. This is especially true since your pressure is remaining the same as the pump is spinning faster. This tells me that your pump is bypassing oil back into the pan via the pressure relief spring.
What I think you need to do is pull the pan (or is it easier to pull the engine on those LT1 F-body's) and put a sensor on the bypass valve to a light on your dash. That way, you could see when it is in bypass mode and we wouldn't have to speculate about anything. Then we could each send you a filter brand of our choice and a qt of your favorite oil and let the testing begin. So, are you up for it?
Don't thank me, I'm always good at saving work for others...
[ January 22, 2003, 04:53 PM: Message edited by: jsharp ]
Chris, media and the bypass spring cause resistance. They impede flow and reduce net pressure. With a higher bypass rating, pressure between the pump and filter will increase, but pressure from the filter to engine will decrease due to the restriction. It won't be a large amount but it does show up on a gauge.
If your engine has a built-in bypass valve then only the media type varies. I haven't compared this type yet. The fixed bypass rating will probably make media differences tough to notice.
David
If your engine has a built-in bypass valve then only the media type varies. I haven't compared this type yet. The fixed bypass rating will probably make media differences tough to notice.
David
You sensor has to be before the filter to show your results. If the sensor was after, then there would be no change with any filter cause of the bypass. Good thing is your oil pump is not working so hard and you're not going into by pass mode like you said.
Leo
Leo
The oil pump has a pressure control valve that maintains a nearly constant output pressure as soon as the pump is turning fast enough to create the pressure to open this control valve. The pressure to the filter will be about constant.
The oil filter (or the oil filter mount on some GM engines...did I get that right?) has an oil filter differential-pressure control valve, also called an oil filter bypass valve. It regulates the maximum pressure drop through the filter. A clean filter with hot oil will have little or no pressure drop, maybe low single-digit psi, and the bypass probably won't open. If the oil is cold or the filter clogged, the pressure differential between the filter inlet and the filter outlet increases, and the bypass opens. The bypass valve will modulate and maintain the set pressure differential range, maybe 7-9 psi, or whatever it's built for, until the oil flow diminishes or the oil gets hot and flows easier through the media causing the pressure differential to decrease. The oil will continue to flow through the filter media even if the bypass valve opens--there's still the 8 psi (or whatever) pushing the oil through.
This oil pressure drop through the filter will show on a pressure gauge downstream of the filter, but you'd really need another pressure gauge upstream of the filter for comparison to know exactly what's happening.
Ken
The oil filter (or the oil filter mount on some GM engines...did I get that right?) has an oil filter differential-pressure control valve, also called an oil filter bypass valve. It regulates the maximum pressure drop through the filter. A clean filter with hot oil will have little or no pressure drop, maybe low single-digit psi, and the bypass probably won't open. If the oil is cold or the filter clogged, the pressure differential between the filter inlet and the filter outlet increases, and the bypass opens. The bypass valve will modulate and maintain the set pressure differential range, maybe 7-9 psi, or whatever it's built for, until the oil flow diminishes or the oil gets hot and flows easier through the media causing the pressure differential to decrease. The oil will continue to flow through the filter media even if the bypass valve opens--there's still the 8 psi (or whatever) pushing the oil through.
This oil pressure drop through the filter will show on a pressure gauge downstream of the filter, but you'd really need another pressure gauge upstream of the filter for comparison to know exactly what's happening.
Ken
I just got back from Kragen, and asked the head tech over there if using a longer filter NOT designated for your car is safe. He said all the oil filters have a regulator in them. This regulator is what sets the oil pressure to your engine specs. If you put in another filter not specified for your engine, you could have oil pressure too low at given engine loads and damage your engine. With that said, I bought the smaller Pennzoil filter cross referenced for our PF44, which is the PZ48. The Fram would be the TF3506.
BTW the K&N was a 1007 they had.
Leo
[ January 25, 2003, 12:19 AM: Message edited by: pedaltothemetal ]
BTW the K&N was a 1007 they had.
Leo
[ January 25, 2003, 12:19 AM: Message edited by: pedaltothemetal ]
Leo, that's partially correct. Some filters have bypass valves. Others don't. Some engines have this valve on the engine in which case a filter bypass isn't required. It isn't anything special, as has been talked about already, it's just a spring. When the pressure differential between the supply and ouput sides of the filter exceed the spring's tension it's pushed open to allow excess oil to bypass the filter. The filter's bypass valve affects total flow but much less than the oil pump and its relief valve. It mainly controls how often your filter is letting unfiltered oil past vs. restricting flow when the oil is cold.
David
Hi Dave,
But the guy said different spring rates for different engines. So if I put a filter with a lower spring rate, then the oil pressure will be too low for my engine. He also said the the major cause of internal leaks in oil filters is separation of the filter element from the end caps. Pennzoil uses aspecially engineered adhesive to assure complete bonding between the filter element and end cap. So does Fram. So I got 4 of the Pennzoil PZ48 filters for $3.99 each. These are the cardboard endcaps. Seems those leaks less because of the bonding.
Leo
I just read this site.http://minimopar.net/oilfilters.html
After reading how bad Frams are, I'm going to return the Pennzoil filters now. I should just stay with Delco from now on.
Leo
[ January 25, 2003, 03:45 AM: Message edited by: pedaltothemetal ]
After reading how bad Frams are, I'm going to return the Pennzoil filters now. I should just stay with Delco from now on.
Leo
[ January 25, 2003, 03:45 AM: Message edited by: pedaltothemetal ]
Patman
Staff member
Leo, that's why when people ask me to search the Purolator catalog for a suitable long filter choice, I look at the bypass valve setting and only recommend longer filters if the bypass is very close to the OEM. And in the case of GM cars, they have the bypass in the block, so filters for them have no bypass anyways.
By the way, don't return to Pennzoil filters, those are Frams! I'd recommend going with a Bosch Premium, Walmart Supertech, Wix, NAPA Gold or of course my favorite K&N.
[ January 25, 2003, 05:35 AM: Message edited by: Patman ]
By the way, don't return to Pennzoil filters, those are Frams! I'd recommend going with a Bosch Premium, Walmart Supertech, Wix, NAPA Gold or of course my favorite K&N.
[ January 25, 2003, 05:35 AM: Message edited by: Patman ]
I would think that a filter like the K&N, Amsoil SDF and similar makes that filter down to less than 20 microns should have a bypass valve even if there is one in the engine, to allow proper oi flow under all conditions.
The one I use in my 2001 GMC 5.3L is the SDF64 and I just recently cut open a used one I took off and it has the bypass in it.
My oil presure is about 40psi idle and 60psi at 55mph, that was with new oil.
The one I use in my 2001 GMC 5.3L is the SDF64 and I just recently cut open a used one I took off and it has the bypass in it.
My oil presure is about 40psi idle and 60psi at 55mph, that was with new oil.
The bypass in the filter has no effect on the engine oil pressure. Pressure is created by resistance to flow of the oil that is being pumped. This resistance is caused by the oiled components of the engine and is varable due to clearances of bearings etc. The bypass only senses differential pressure created by the filter media. The more restriction the media has, the higher the differential pressure will be. Once it has reached the preset pressure of the bypass valve spring, the bypass will open and allow the unfiltered oil to flow to the engine. In normal operation the oil pump will supply more than enough volumn in a healthy engine to make the pressure reach a level that the oil pressure relief valve in the oil pump to relieve any excess pressure. This valve is preset at the factory. If the oil pressure relief valve is set at 60 psi, that should be your maximum oil pressure in a engine at normal operating temperature.
Regards,
Regards,
My LS1 engine has 2 pressure relief valves, one in the oil pump and one in the oil filter base.
[ January 25, 2003, 10:11 AM: Message edited by: Mike ]
[ January 25, 2003, 10:11 AM: Message edited by: Mike ]
Got it guys! Thanks! Guess those guys at the parts dealers only know parts and not mechanics. I compared the Pennzoil/Fram to my PF44 Delco when I got home. The Delco is built better by just looking inside. There are way more holes letting the filtered oil out. Been using it exclusively since I got my car in late '97 so will stick with it now. I saw the K&Ns there. Seeems they have a very thick shell because it was needed to accomodate a wrench so the filter won't collapse. I'll take a closer look at it when I go back to Kragen today. You know I spend an hour just looking at filters yesterday, and you know why after spending time here!
Thanks,
Leo
Thanks,
Leo
The Mobil1 filter is a cousin to the K&N--also with a very sturdy can. Both made by Champion Labs.
The hunky cans are a design spec to accomodate startup pressures of many thousands of on-off cycles. The 1" nut on the K&N is a nice touch for installers. For anyone working in a cramped space, it's quite easy to insert a socket on an exension to the filter, rather than wrangling a filter wrench.
The two filters do not share the same media. Similar synthetics, but not identical. This is the "more flow" selling point for the K&N. Not quite as efficient as the Mobil1's advertised 10 microns--I think that the K&N is 15 microns--but perhaps a better balance or compromise in overall functionality.
I just installed a K&N for the first time on my new truck engine. My gauge is just a dummy "yes or no" on the oil pressure, so I don't have any value to monitor or report. I just made the leap of faith that the K&N reputation will work for me.
Patman, are you sure that your pressure gauge is functioning properly?
The hunky cans are a design spec to accomodate startup pressures of many thousands of on-off cycles. The 1" nut on the K&N is a nice touch for installers. For anyone working in a cramped space, it's quite easy to insert a socket on an exension to the filter, rather than wrangling a filter wrench.
The two filters do not share the same media. Similar synthetics, but not identical. This is the "more flow" selling point for the K&N. Not quite as efficient as the Mobil1's advertised 10 microns--I think that the K&N is 15 microns--but perhaps a better balance or compromise in overall functionality.
I just installed a K&N for the first time on my new truck engine. My gauge is just a dummy "yes or no" on the oil pressure, so I don't have any value to monitor or report. I just made the leap of faith that the K&N reputation will work for me.
Patman, are you sure that your pressure gauge is functioning properly?
Patman
Staff member
Yes, I'm pretty sure my oil pressure gauge works fine. It shows close to 60psi on a cold start, slowly moving down as the oil warms up to where it shows just under 20 at idle. Today I tried a few more hard runs, and would notice when the trans first downshifted (at 60mph) the pressure would spike up by about 5psi, but then settle back down to a steady point even as the rpms climbed back up to the redline. I wish the roads weren't slightly slippery I would've tried a hard run from a dead stop and watched the gauge.
Patman,
I'm starting to think your oil pressure drops at WOT don't have anything to do with the filter. This sounds more like a stopped up pickup screen or a dirty oil pan. If you haven't already, drop the oil pan and see if there's any crap near the pickup screen that might block it under high rpms from the pump sucking more oil and bringing any gunk with it. This is something that I highly doubt even auto-rx could take care of. The first thing you could do is hook up a mechanical pressure guage and see what the actual pressure is and go from there. No matter what it is I wouldn't like getting only 45psi close to 6k rpm in a well-maintained, low mileage engine like your LT1. My friend's 98 S10 4.3 with 95k and my 318 Jeep both stay right around 60psi at WOT, both having real guages. And for both of these engines redline is about 5k rpm.
Jason
I'm starting to think your oil pressure drops at WOT don't have anything to do with the filter. This sounds more like a stopped up pickup screen or a dirty oil pan. If you haven't already, drop the oil pan and see if there's any crap near the pickup screen that might block it under high rpms from the pump sucking more oil and bringing any gunk with it. This is something that I highly doubt even auto-rx could take care of. The first thing you could do is hook up a mechanical pressure guage and see what the actual pressure is and go from there. No matter what it is I wouldn't like getting only 45psi close to 6k rpm in a well-maintained, low mileage engine like your LT1. My friend's 98 S10 4.3 with 95k and my 318 Jeep both stay right around 60psi at WOT, both having real guages. And for both of these engines redline is about 5k rpm.
Jason
hey patman I am doing an interval of auto rx with the ac delco filter and I noticed the same thing only difference is I get about 25psi at idle, cold start its close to 60psi, normal driving its about 40 psi at 1500 and past 2000 and towards redline it stays about 45psi. Anyone else have an LT1? what are you using?
[ January 26, 2003, 01:14 AM: Message edited by: 94 formula ]
[ January 26, 2003, 01:14 AM: Message edited by: 94 formula ]
Patman
Staff member
But my pressure isn't dropping at full throttle, it's simply staying where it was before. I've also heard that as long as I have better than 10psi for every 1500rpm, I'm safe. Sounds like I have no worries here.
- Status
Similar threads
