NAPA Gold has an up front bypass valve while the NAPA Platinum has a dome end bypass valve. A lot of you guys say the dome end bypass valve is no good because the oil back washes over the dirty filter element when in bypass. Why doesn't NAPA/WIX make them both with the up front bypass valve ?
Up Front Vs. Dome End Bypass Valves
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Well, I watched several filter videos of the NAPA...ProSelect, Silver, Gold & Platinum. All look quite good and maybe, I'd like to create my own by using the Gold construction and the Platinum filtration media...IDK!
I do like to cut open my filters after useage and see how it held up. This either causes concerns or confidence! I hope the latter but lately, I have found the Purolator Classic and PureOne have started to look cheaper in the filter media than before. Though I haven't had any issues!
I do like to cut open my filters after useage and see how it held up. This either causes concerns or confidence! I hope the latter but lately, I have found the Purolator Classic and PureOne have started to look cheaper in the filter media than before. Though I haven't had any issues!
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^ I was about to link that topic.
As per our last discussion - no one really knows. My own anecdotal take: Dome end may be cheaper to manufacture, and will be the choice unless a manufacturer specifies otherwise. Motorcraft 910's have a thread-end bypass (As it is specified by Ford), but I could purchase a Fram of the same specs with a dome-end bypass.
It is very difficult to prove one design's superiority over the other. Most of all realize - as long as you keep your engine clean with regular OCIs, the bypass valve will rarely be used except in very cold start-ups.
As per our last discussion - no one really knows. My own anecdotal take: Dome end may be cheaper to manufacture, and will be the choice unless a manufacturer specifies otherwise. Motorcraft 910's have a thread-end bypass (As it is specified by Ford), but I could purchase a Fram of the same specs with a dome-end bypass.
It is very difficult to prove one design's superiority over the other. Most of all realize - as long as you keep your engine clean with regular OCIs, the bypass valve will rarely be used except in very cold start-ups.
Dome-end valves can be made more precise at the same cost. Dirt is pinned to the filter medium before the bypass opens, and is held there during bypass. Base-end bypass just doesn't seem to have the advantages often touted, IMO.
Nothing WRONG with them, but I'd never go out of my way to buy them.
Nothing WRONG with them, but I'd never go out of my way to buy them.
Originally Posted By: Hyde244
^ I was about to link that topic.
As per our last discussion - no one really knows. My own anecdotal take: Dome end may be cheaper to manufacture, and will be the choice unless a manufacturer specifies otherwise. Motorcraft 910's have a thread-end bypass (As it is specified by Ford), but I could purchase a Fram of the same specs with a dome-end bypass.
It is very difficult to prove one design's superiority over the other. Most of all realize - as long as you keep your engine clean with regular OCIs, the bypass valve will rarely be used except in very cold start-ups.
The bypass may be used more often than we know. Fast accelerations, sudden rpm surges when passing etc may all be causes. A guy here asked his engineer friend at Purolator about it and said basically everyone would like to know.. Even them.
^ I was about to link that topic.
As per our last discussion - no one really knows. My own anecdotal take: Dome end may be cheaper to manufacture, and will be the choice unless a manufacturer specifies otherwise. Motorcraft 910's have a thread-end bypass (As it is specified by Ford), but I could purchase a Fram of the same specs with a dome-end bypass.
It is very difficult to prove one design's superiority over the other. Most of all realize - as long as you keep your engine clean with regular OCIs, the bypass valve will rarely be used except in very cold start-ups.
The bypass may be used more often than we know. Fast accelerations, sudden rpm surges when passing etc may all be causes. A guy here asked his engineer friend at Purolator about it and said basically everyone would like to know.. Even them.
Ford and Chrysler both think enough of the thread end bypass to spec it in their branded aftermarket filters.
I suspect bypasses at least crack open more than we might think. When I experimented with a compatable non spec filter with a bypass double the spec'd rating, I got some bad noise at cold start up, but it wasn't start up rattle it was running noise after start up cold. It didn't happen every time. I suspected the high bypass wasn't cracking and was causing a little oil starvation. I had to take it off after about 500 miles for this reason.
But like was posted, nobody really knows. I like thread end bypasses but don't consider it a deal breaker by any means. All the visible grit I've seen stuck to filter media after dissection did not appear to me like it was going to come off regardless of the bypass location.
I suspect bypasses at least crack open more than we might think. When I experimented with a compatable non spec filter with a bypass double the spec'd rating, I got some bad noise at cold start up, but it wasn't start up rattle it was running noise after start up cold. It didn't happen every time. I suspected the high bypass wasn't cracking and was causing a little oil starvation. I had to take it off after about 500 miles for this reason.
But like was posted, nobody really knows. I like thread end bypasses but don't consider it a deal breaker by any means. All the visible grit I've seen stuck to filter media after dissection did not appear to me like it was going to come off regardless of the bypass location.
Originally Posted By: KCJeep
When I experimented with a compatable non spec filter with a bypass double the spec'd rating, I got some bad noise at cold start up, but it wasn't start up rattle it was running noise after start up cold. It didn't happen every time. I suspected the high bypass wasn't cracking and was causing a little oil starvation. I had to take it off after about 500 miles for this reason.
Was this the Fram Extra Guard that you posted pics of?
When I experimented with a compatable non spec filter with a bypass double the spec'd rating, I got some bad noise at cold start up, but it wasn't start up rattle it was running noise after start up cold. It didn't happen every time. I suspected the high bypass wasn't cracking and was causing a little oil starvation. I had to take it off after about 500 miles for this reason.
Was this the Fram Extra Guard that you posted pics of?
No I don't remember taking pics of that one. It was a Liberty diesel filter, the PH8316. It had two ADBV's, and is a ringer for an FL-400s but the bypass setting is much higher than the FL-400s or any other "spec" filter, around 23 psi IIRC?
I was hoping the double ADBV's would solve my start up issue but the bypass was apparently a problem. That was before I discovered the Napa Silvers worked so well. I haven't experimented with another filter since I found the Silvers.
I was hoping the double ADBV's would solve my start up issue but the bypass was apparently a problem. That was before I discovered the Napa Silvers worked so well. I haven't experimented with another filter since I found the Silvers.
Base end bypass valves could potentially help with filters that are orientated with the base up if debris sloughs off the media when the engine is stopped and falls down into the dome end of filter. If there is a lot of debris collected in the dome end, then it's possible a dome end bypass valve could let some of that debris through on initial start-up. That's the whole reason that Ford specs a base end bypass valve on some filters, because those filter applications are orientated at about 45 deg with base up.
^ And they also spec thread-end bypass valves for filters that are perpendicular to the ground, such as the Ford Focus.
I know someone on the forums has actually tested PSI of oil filters - would appreciate it if someone were able to drag up the link for that thread.
In general, longest time a bypass valve has been shown to operate in normal operation is during a cold start-up. Of course the valve will open if you go full throttle, but anything above 5,500 RPMs would hardly be normal operation.
I know someone on the forums has actually tested PSI of oil filters - would appreciate it if someone were able to drag up the link for that thread.
In general, longest time a bypass valve has been shown to operate in normal operation is during a cold start-up. Of course the valve will open if you go full throttle, but anything above 5,500 RPMs would hardly be normal operation.
Originally Posted By: Hyde244
^ And they also spec thread-end bypass valves for filters that are perpendicular to the ground, such as the Ford Focus.
I know someone on the forums has actually tested PSI of oil filters - would appreciate it if someone were able to drag up the link for that thread.
In general, longest time a bypass valve has been shown to operate in normal operation is during a cold start-up. Of course the valve will open if you go full throttle, but anything above 5,500 RPMs would hardly be normal operation.
That would be our member Jim Allen, you can search for his threads.
The filter's bypass valve should not open at red line if the oil is at full operating temperature (ie, ~200 deg F). High revs with cold oil, probably so.
^ And they also spec thread-end bypass valves for filters that are perpendicular to the ground, such as the Ford Focus.
I know someone on the forums has actually tested PSI of oil filters - would appreciate it if someone were able to drag up the link for that thread.
In general, longest time a bypass valve has been shown to operate in normal operation is during a cold start-up. Of course the valve will open if you go full throttle, but anything above 5,500 RPMs would hardly be normal operation.
That would be our member Jim Allen, you can search for his threads.
The filter's bypass valve should not open at red line if the oil is at full operating temperature (ie, ~200 deg F). High revs with cold oil, probably so.
If the dome of your oil filter is full of enough crud to worry about it going into the engine then I would say you have a problem that no bypass location is going to fix.
https://bobistheoilguy.com/forums/ubbthreads.php/topics/3067617/1
This may be the thread your looking for.
This may be the thread your looking for.
That NAPA Gold video is excellent. I had no idea how a bypass valve worked until I watched that video.
Originally Posted By: jhellwig
If the dome of your oil filter is full of enough crud to worry about it going into the engine then I would say you have a problem that no bypass location is going to fix.
Agreed. Its a complete non-issue for most engines, and I personally think that dome-end valves look more reliable. No hard data to back that up, but they are certainly simpler.
And DO NOT FORGET that in order for the bypass valve to open at all, oil must ALREADY be flowing through the media at a high rate- high enough to create the maximum allowable pressure differential across the media, and therefore all the gunk is firmly pinned to the media and won't be "sloughing" ANYWHERE.
If the dome of your oil filter is full of enough crud to worry about it going into the engine then I would say you have a problem that no bypass location is going to fix.
Agreed. Its a complete non-issue for most engines, and I personally think that dome-end valves look more reliable. No hard data to back that up, but they are certainly simpler.
And DO NOT FORGET that in order for the bypass valve to open at all, oil must ALREADY be flowing through the media at a high rate- high enough to create the maximum allowable pressure differential across the media, and therefore all the gunk is firmly pinned to the media and won't be "sloughing" ANYWHERE.
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