Full flow oil filtration

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Ron LaDow
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Re: Full flow oil filtration

#46 Post by Ron LaDow »

Norm Miller wrote: Wed Apr 24, 2019 12:18 pm Methinks the engines work both ways so get out and drive them.
Absolutely! And some folks like the intake roar of carbs with no filters, too.
But don't hand out B.S. about how bearings run just as well in contaminated oil, and it won't affect engine life and all the rest of the nonsense.
Ron LaDow
www.precisionmatters.biz

James Learmonth
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Re: Full flow oil filtration

#47 Post by James Learmonth »

John Jenkins,
I heard it this way: The most evenly distributed commodity in the world is commonsense: Everyone knows they have enough.
I will fight to save my Premat filter adapter. Over 157,000 miles.

Jim Learmonth
65C Coupe
Houston, TX

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David Jones
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Re: Full flow oil filtration

#48 Post by David Jones »

I am not going to come down either side of this argument/discussion but I will make a few points. My first VW 1200 beetle went about 80K miles before I replaced it with a VW rebuilt unit before leaving for the UK after my tour in Germany. That engine lasted about 5 years as a daily driver and sometimes rally and chase car when the car failed the UK road test due to rust. Only things that really went wrong were frequent clutch disc changes and a dropped wrist pin clip that cause a rather large groove in one cylinder. Quickly fixed in 67 with a new matching piston and cylinder from the local VW dealer. No filter and no multigrade oils. Probably less than optimum miles for a VW 1200 engine back then but it was driven everywhere with a heavy right foot.
Fast forward to 81 and I started racing Formula Vee and same engine but now running over 6K rpm and a full flow oil filter. Had to change rod bearings every 6 races and mains every 12, bearing were usually showing signs of over use. Probably 200 to 300 miles each race weekend. A couple of years into racing I switched to synthetic oil and bearing life went up so that after 24 races all the bearings still looked like new. After one engine rebuild and after dyno run then a race practice session I pulled the valve covers to adjust the valves and was horrified to find flecks of silver in the oil in the covers. Not having a spare engine all I could do was change the oil and put my trust in my engine builder. I finished the race weekend with no problems other than my total lack of success on my one and only visit to Laguna Seca.
Of all the 356 engines I have used and abused over the years I give two extreme examples. My 59 coupe has the oil pump cover tapped for full flow with the return to the third piece, after an oil change the oil is very dark in about 500 miles, the engine has a lot of miles and uses oil. My 64C has a mongrel big bore engine I built about 15 years ago and has been in three different cars, runs a C/SC wide lobe cam, Solex carbs and stock oil filter. After 1000 miles the oil still looks like dark honey. I have no doubt the 59 engine stays alive because of oil transfusions and the full flow filter and the 64 engine is still young enough to not overheat the oil or suffer excessive blow by.
I have personally given up on full flow oil filters for street engines as I have for synthetic oil because I will never see the return on investment before I "hop the twig" as so succinctly put by one John Cleese. I can change my oil three times a year for the next 10 years for less than the cost of a full flow filter set up and an electric tach. There is no question that a full flow filter is beneficial to engine longevity but it is only worth it if you are sure you want your engine to outlive you.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715

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GregVandenbussche
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Re: Full flow oil filtration

#49 Post by GregVandenbussche »

Had Ron full flow oil pump cover, smashed it on a deep cattle guard on a rally, instant pump and oil extraction :shock: , took a good 2hr to get the cover back since all but one stud teared down (the nut teared down on this one), had to be creative and use cheese head screw from the tin to re-attach the cover to drive our 5hr way back to SF... i now have Ron cover with IN/Out for oil, bypass valve, and use mobile 1 giant filters on a filter mount inside the engine bay.
Bt5 Super - used to be fjord green, was painted brass, then brown... sadness

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Ron LaDow
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Re: Full flow oil filtration

#50 Post by Ron LaDow »

GregVandenbussche wrote: Mon Apr 29, 2019 10:35 pm Had Ron full flow oil pump cover, smashed it on a deep cattle guard on a rally, instant pump and oil extraction...
I have to admit that the Full Flow Adapter was designed for street use. But I'm glad you still have clean oil.
Ron LaDow
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Steve Hatfield
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Re: Full flow oil filtration

#51 Post by Steve Hatfield »

I tore one off too. Leaving a Fourbucks with a deep dip onto the street. Loud ‘thump’ followed by a five-quart instant pavement dusche. Flatbed ride home a couple of miles. Replaced the studs but later discovered a fractured oil pump drive gear tang; something I should have caught on initial post-incident inspection. I’ve since developed a better eye for vertical road deviations. And I now carry essential parts, oil and tools just in case.
Steve Hatfield
Fort Walton Beach, FL
'63 S90 Sunroof Coupe
'06 997S Coupe

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Harlan Halsey
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Re: Full flow oil filtration

#52 Post by Harlan Halsey »

All that fun because you were taken in by the chicken little marketing, bought the snake oil and drank it. Just read the second post in this thread and you will be cured!

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Wes Bender
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Re: Full flow oil filtration

#53 Post by Wes Bender »

I suspect that's a little over the top, Harlan. Something we don't see very often here on the forum.
Some days it's just not worth chewing through the restraints.....

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Mike Wilson
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Re: Full flow oil filtration

#54 Post by Mike Wilson »

I agree.
Mike Wilson
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Greg Bryan
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Re: Full flow oil filtration

#55 Post by Greg Bryan »

Folks - let's not go off the rails. We're talking about old cars here - no need for name calling and raised blood pressure - it's just not that important …
If you want to buy a full flow filter, then do, by all means. If you don't, spend your money on loud exhaust.
Greg Bryan

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Eric McKinley
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Re: Full flow oil filtration

#56 Post by Eric McKinley »

Can I have both?

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Greg Bryan
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Re: Full flow oil filtration

#57 Post by Greg Bryan »

Both? By all means!
And I'm sure there are other things you need, too ...
Greg Bryan

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Ron LaDow
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Re: Full flow oil filtration

#58 Post by Ron LaDow »

There is no 'snake oil' regarding what bearings prefer for lubrication: The cleaner the better, everywhere and always. Plain bearings, rolling-element bearing; every possible bearing you can imagine in every possible application lasts longer with less crap in the lubrication than it does with more crap. The data are 100% in agreement: Cleaner = longer bearing life. Period. And the 616 engine has no special dispensation; 616 bearings wear and fail as a result of dirty oil like those in a Model T or those in the latest RR turbo fan. This is not open to dispute; claims otherwise are at odds with all data and should be treated as claims regarding UFOs in the backyard.
I had full-flows on several of my cars in order to prolong the life of the bearing surfaces long before designing the Pre Mat parts; those parts are the result of that desire, selling them is not the cause.
Yes, the design compromises on the Pre Mat Full Flow (favoring keeping the filter full on start up) means it is possible to back into something or fly over (and land on something) and lose the filter. I live in SF, renown for sharp curbs and hills; mine have survived for 15 years with no problem, so I'm not sure the compromise should have been biased otherwise. Sorry about the loss, you guys, but designing for those circumstances means other compromises; not sure how to do that. Regardless, that issue is irrelevant to providing clean oil to the bearings.
The claim of 7% filtration for the stock filter *IS* BS; it's too generous. The claim that after X minutes, 'it's all clean' assumes the 'clean' 7% stays that way and 'joins forces with that other 7% filtered oil, and then the other... (etc)'. It doesn't; that oil went around again and picked up all the crap the contaminated oil generated from wearing out the bearings becoming yet one more '7% of clean oil' that became (re)contaminated oil. So much for claims that 'all the oil finally gets filtered'. No, it doesn't. It gets dirtier and dirtier. As you might notice when you pull the dipstick at, oh, 750 miles after an oil change.
This is not a matter of opinion, it is a matter of data and fact. You may choose to provide dirtier oil to the detriment of the engine's bearings, as do those who chose no air filters to the detriment of the rings, but don't claim it to be other than personal choice, devoid of supporting data. It is your property to deal with as you please. But claiming that cleaner oil is not preferable to dirty oil is simply BS and (Greg?) I don't think spreading BS is our purpose here. That claim is simply BS.
Anyone else remember Miami Air and the his claims that pop-riveting his longs were as good as welding them? BS and deserved to be called as such.
Ron LaDow
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Martin Benade
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Re: Full flow oil filtration

#59 Post by Martin Benade »

Ron, this reminds me of years ago when trying to help a loved one not do drugs and alchohol. I thought if I could just word my explanation properly, she would understand and get all better. Turns out that some things, no matter how sensible and fact-filled the explanation is, cannot be accepted by someone that doesn't want to. You might just have to let it go.
Cleveland Ohio
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56 VW
02 IS 300
04 Sienna

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Alan Hall
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Re: Full flow oil filtration

#60 Post by Alan Hall »

Ron, I don't believe anyone claimed that the oil all got "clean" after X minutes but rather it essentially stops getting dirtier after X minutes. I will try to briefly explain, If we assume the pump moves 4 qts per minute of oil and the engine holds 4 quarts of oil and the engine is generating crud at the rate of x particles per minute the bypass filter equipped engine oil gets dirtier until the number of particles in the oil reaches approximately 14x at which time filtering 7 percent of the oil is removing x particles per minute (7 % of14x) which is the same rate the engine is generating particles. The amount of time for the engine oil to build up to a contamination level of 14x would take about 45 minutes or so using our assumptions. From then on the rate of contamination increase would be minimal based on filter efficiency and the rate of increase (not the level of contamination) would be approx. the same as a full flow system. On the other hand, an engine with no filter at all would reach a contamination level of 14x in 14 minutes and would continue to increase at a rate of x particles per minute until you changed the oil.

That said I still agree with you that cleaner is better and that full flow systems give cleaner oil, but a bypass system is way better than no filter and does not significantly get "dirtier and dirtier" as you claim.

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