IMO
Intersting thought but.....
The high rate of wear is from:
No oil flow and moving cold parts on startup
Not enough warm up time to stabilize temp's before hitting it.
Not just bearing inserts, but pistons, rings, cam and lifters........
Plugging the block bypass in a SBC
- Thread starter Big O Dave
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Intersting thought but.....
The high rate of wear is from:
No oil flow and moving cold parts on startup
Not enough warm up time to stabilize temp's before hitting it.
Not just bearing inserts, but pistons, rings, cam and lifters........
I agree this mod might not be for everyone. It is not a good idea to rev the motor very high until it builds up some temperature. And its also not a good idea in if you drive in below freezing temperature very much.
But I do own and have owned higher performance street motors that I have block the oil filter bypass that have been together for more than a decade.
I have yet see a collapsed media or center tube on a ACDelco, Wix, or Moroso oil filter on any motor I have done this to. And I have cut open many in the 25 years I've been doing this mod.
Anyone here ever wonder why most wear on street motors occurs when they are 1st started up? My theory is it because the oil filter is being bypassed a fair amount on a cold motor. How else do you explain the higher wear that occurs on motors mostly driven on short trips?
I once took apart a motor that only had 40K something miles on it in a Ford truck. It spent much of its life driven less than 2 miles each way to and from work. The guy had a well documented 3K miles oil change history. The wear in that motor was incredible.
I also find it interesting that some European and some diesel motors have a oil filter bypass setting above 29 PSI.
I would hope any engine would have close as possible tolerances reguardless of the clearances.
The bypassed oil is filtered used oil, that was good enough for you when you shut the car off.
It is circulated unfiltered for a short time, if at all. The bypass doesn't operate on every start. It is a safety feature, so you don't blow the filter walls out, or rupture it.
I'd leave it stock, but check that the valve and spring are OK.
It is circulated unfiltered for a short time, if at all. The bypass doesn't operate on every start. It is a safety feature, so you don't blow the filter walls out, or rupture it.
I'd leave it stock, but check that the valve and spring are OK.
As much as I idolized Lingenfelter, I have to disagree with plugging the bypass on a street engine. I will take unfiltered oil over no oil anyday. If you are that concerned with filtration, use a bypass filter.
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The same thing that happens in any engine, at any rpm, where the filter is in bypass.
In my testing ..the bypass valve isn't effected by viscosity, nor temperature. The filter is pretty much a non issue in most cases. YMMV
The old filter bypass. Here is my take on it. I do it to my SBC performance engines because I use a hi volume/pressure pump, & want all my oil in the filters. I use dual remote mount filters. I also use a accumalator. At start up, parts, oil & coolant are cold. Parts(like pistons) must warm to fit right. if the by-pass opens, i am passing unfiltered oil into my hi dollar parts, & the bad stuff can lodge & do heavy damge as the parts expand. The biggest risk, is reving (thus increase in pressure) & blowing a filter(s)when the oil is cold. Any one who has spent any time at the track has a least seen a blown filter. if you are not willing to change your oil & filters after every event,then leave the plug alone.
GM probably had one or two bright people consider whether there should or shouldn't be a bypass since they started making the SBC in 1955(? around that time wasn't it?).
My guess is that for a daily driven vehicle in cold to hot conditions, GM got it right.
Lingenfelter may have gotten it right for race vehicles in warm conditions....but I don't know whether his book contained a warning about for which types and uses of vehicles this would be appropriate.
Every manufacturer I am aware of employs a bypass for the filter system. That's alot of auto manufacturers' pointy-headed nerds in back rooms around the world thinking it's a good idea.
I'm going to side with the nerds on this one.
My guess is that for a daily driven vehicle in cold to hot conditions, GM got it right.
Lingenfelter may have gotten it right for race vehicles in warm conditions....but I don't know whether his book contained a warning about for which types and uses of vehicles this would be appropriate.
Every manufacturer I am aware of employs a bypass for the filter system. That's alot of auto manufacturers' pointy-headed nerds in back rooms around the world thinking it's a good idea.
I'm going to side with the nerds on this one.
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No. The biggest risk is collapsing the media internally and driving your entire event with unfiltered oil putting a new finish on everything inside the engine. If you merely blow the can ..you'll at least know it and should be able to shut it down. A bypass won't let this happen.
Amen! If your filter clogs and stops flow, hopefully you'll see your oil pressure gauge and shut the engine off immediately. But if you destroy the element in a way that does not stop flow, how will you know before you cut the filter open? You could conceivably push trapped particles through the media and not notice it even if you did cut the filter open and examine it.
I think a better approach is to try to avoid conditions that open the bypass, but leave the bypass in place for circumstances beyond your control.
Edit: however, if you install remote oil filter(s) or an oil cooler, blocking the bypass is necessary because the pressure drop due to the lines may cause the bypass to be open just about all the time.
My understanding is that the factory bypass valve opens when there is >4psi difference between the input and output of the filter. Can anyone confirm or deny that? It might be worth looking into getting a spring that is slightly stiffer considering Bob's oil filter tests.
WOW...This is almost like an oil thread. John and the Grump know engines. Bottom line..The bypass was created for the Normal folk, who start the commute vehicle, hit the highway cold and don't know any better than to blow the filter off of the block. Enthusiasts allow the pride and joy to reach operating temperature before cruise speeds. Driving style and climate are good indicators if the bypass is for you. Maybe run a dual remote filter?
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