[302crossram]

??

[JTS]

A step up from the PF 64 , I would like to think.

[302crossram]

Originally Posted by JTS

A step up from the PF 64 , I would like to think.

IIRC, the pressure relief on the Gold is higher so no bueno ???

[Mark114]

PF64. The PF64 has a 22 psi bypass pressure. The UPF64R filter has a 35 psi bypass pressure. There are numerous discussions in the forums comparing these filters if you want to search for them.

[cosmok]

Search resulted in no help. Why is the higher bypass pressure a problem?

[WhiteMale]

If they wanted you to use a UPF64R that's what would be in the manual.

[Gunkk]

PF64.

There's no way I'd mess with a different bypass psi. The oiling system is fragile enough as it is. Enjoy your denied warranty claim.

[D.O.M.D1]

im debating if i should get a handful, for future oil changes, and it looks like the UP64R is a little taller, by a few milimeters, and its ideal for the V8s and the supercharged V8, either way, its all good

[LT4Greg]

The gold GM filter is for the LS engines and I would stay with the regular GM filter for the LT engines. Or you could go with the Gold Napa or the Mobil 1 filters. I have had no problems with either of those in my LT4 engine.

[Callaway SC630]

Originally Posted by D.O.M.D1

im debating if i should get a handful, for future oil changes, and it looks like the UP64R is a little taller, by a few milimeters, and its ideal for the V8s and the supercharged V8, either way, its all good

If I were you, I would get at least a dozen.

[arpad_m]

I don't understand why you guys want to use UPF64R all of a sudden, when every piece of documentation calls for PF64. The price difference is negligible, especially considering the price of oil and the typical frequency of oil changes even among the most paranoid.

This isn't the same as the oil debate where there are objective standards and oils can exceed those with or without certification. The UPF64R has a different bypass psi, ergo behavior, and I have yet to see actual test results that would prove its (assumed) superiority to the PF64 (that itself has had a quite a few revisions over the years).

With all that said, I would be happy to read some educational materials on these specific filter beyond the handwavy marketing fluff that many threads in the past linked to. As a single data point, I have used PF64 since the day I took delivery and never had an issue.

[ctrlz]

Originally Posted by Mark114

PF64. The PF64 has a 22 psi bypass pressure. The UPF64R filter has a 35 psi bypass pressure. There are numerous discussions in the forums comparing these filters if you want to search for them.

You would kinda need to see how this UPF filter affects oil pressure in the car under varying conditions.
My car runs about 40 psi with 5w-30 once warmed up and under light load/cruise. This is with the PF64, and this covers probably 95% of my driving.

The UPF probably has different media plus the higher bypass setting. 35 is a little close to 40 for my comfort. The filter is going to bypass when either the oil is too thick to get through the media, or the media is too clogged. Now that 35 number may mean it STARTS to bypass at 35 and is FULLY OPEN at a higher pressure. I'm not sure, but flow volume would be important there. Someone else can run the experiment and let us know. A valve like this will have a "cracking pressure" and a "fully open pressure."

[easttxss]

Originally Posted by ctrlz

You would kinda need to see how this UPF filter affects oil pressure in the car under varying conditions.
My car runs about 40 psi with 5w-30 once warmed up and under light load/cruise. This is with the PF64, and this covers probably 95% of my driving.

The UPF probably has different media plus the higher bypass setting. 35 is a little close to 40 for my comfort. The filter is going to bypass when either the oil is too thick to get through the media, or the media is too clogged. Now that 35 number may mean it STARTS to bypass at 35 and is FULLY OPEN at a higher pressure. I'm not sure, but flow volume would be important there. Someone else can run the experiment and let us know. A valve like this will have a "cracking pressure" and a "fully open pressure."

Bypass pressure is not the same as system pressure, otherwise the filter would would be in a constant state of bypass at 22psi

[Mark114]

A post from a different thread on oil filters. I’m not an expert but this seems to imply that a higher bypass pressure could result in oil starvation.

https://www.camaro6.com/forums/showthread.php?t=566061

Originally Posted by KLG

You are welcome for that post, sharing information helps us all.

OK, I will try to answer your questions, but I am not an expert on the LT1/LT4 engines. These modern engines are a lot different than the Fords & Chevys I worked on in the 70’s and 80’s.

Yes, the oil goes through the filter first after exiting the oil pump. I believe this is typical of most automotive lubrication systems, but I won’t swear to it.

It is confusing, but engine oil pressure is not the same as the oil filter by-pass pressure. For example, assume we are using a PF64 and the oil enters the oil filter at 40 psi and exits the filter at say 35 psi, all is good, the by-pass valve has no reason to open since the pressure drop across the filter is only 5 psi. However, if oil enters the filter at 40 psi, but would exit the filter at 17 psi, then the by-pass valve would open because the pressure drop across the filter is greater than the by-pass pressure setting of 22 psi.

What GM is concerned about is that these modern engines see high oil pressure at times. So, during those conditions of high oil pressure, the pressure drop across the filter could also be high for a short time which would open the by-pass valve of an oil filter with a setting of only 15 psi. So, GM increased the oil filter by-pass spec by about 50% to the current 22 psi rating to reduce the chances of unfiltered oil going through the engine.

For most of us, the by-pass will not open, even if you elect to use a filter with a lower by-pass pressure. You need situations such as a cold start under cold conditions, high viscosity oil, flogging the vehicle immediately after a cold start, clogged oil filter, etc. And even if it does by-pass, it is probably for only a short period of time.

However, to be cautious, I prefer a filter with the correct by-pass pressure. Filters such as: AC PF64; NAPA Gold 100290; Wix WL10290xp; Fram Ultra XG12060, meet the GM by-pass specification. I am sure there are other filters that meet the specification too.

Anyway, I hope this helps.