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Wildthings
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PostPosted: Wed May 30, 2012 5:59 pm    Post subject: Reply with quote

udidwht wrote:
Wildthings wrote:
FV195 wrote:
I have been running Brad Penn 50wt. green oil. thime to change it, came across a deal I could not pass up.
5qts, royal purple 20/50 and a RP filter, HP1 size... $30 at pepboys


I am no lover of thin oils as many who read this thread know, but why the insistence on 50wt? VW doesn't recommend 50wt for use at any temperature and only recommends 20w50 up to 80°F or so. I would think with 50wt you would be having noticeable slow cranking whenever the temperatures get down below 60°F.

I see no reason to go for extremes on selecting an oil for an ACVW, and I consider 50wt, 20w50, and 0w20 all to be extremes.


That was due to the fact that multi grade oils back then differed greatly from those of today. If you look at the later manuals as time went by the multi grades coverage went up on the temperature charts.


And my Bentley published in 1991, doesn't recommend 20w50 over 15w40 so why go thicker? Even at the highest temperatures on their scale they still recommend 40 wt, not 50wt, so once again why go thicker? As you imply oils maintain their viscosity better today than in times past, then why not go with a 10w40 or 5w40, or even a 10w30? If you are sitting for an hour a day in afternoon rush hour traffic at temperatures that typically run above 100°F or are crawling over rocks in the desert at the same temps and refuse to go to a synthetic then a 20w50 dyno may be for you, but most of the rest of us just don't need it.
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udidwht
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PostPosted: Sat Jun 02, 2012 12:49 am    Post subject: Reply with quote

Wildthings wrote:
udidwht wrote:
Wildthings wrote:
FV195 wrote:
I have been running Brad Penn 50wt. green oil. thime to change it, came across a deal I could not pass up.
5qts, royal purple 20/50 and a RP filter, HP1 size... $30 at pepboys


I am no lover of thin oils as many who read this thread know, but why the insistence on 50wt? VW doesn't recommend 50wt for use at any temperature and only recommends 20w50 up to 80°F or so. I would think with 50wt you would be having noticeable slow cranking whenever the temperatures get down below 60°F.

I see no reason to go for extremes on selecting an oil for an ACVW, and I consider 50wt, 20w50, and 0w20 all to be extremes.


That was due to the fact that multi grade oils back then differed greatly from those of today. If you look at the later manuals as time went by the multi grades coverage went up on the temperature charts.


And my Bentley published in 1991, doesn't recommend 20w50 over 15w40 so why go thicker? Even at the highest temperatures on their scale they still recommend 40 wt, not 50wt, so once again why go thicker? As you imply oils maintain their viscosity better today than in times past, then why not go with a 10w40 or 5w40, or even a 10w30? If you are sitting for an hour a day in afternoon rush hour traffic at temperatures that typically run above 100°F or are crawling over rocks in the desert at the same temps and refuse to go to a synthetic then a 20w50 dyno may be for you, but most of the rest of us just don't need it.


Nor would it (Bentley) or should I say should. After all the Bentley was printed over 20 years ago. It's basically a reprint of previous Bentleys (unchanged). What one runs should be based on the conditions they will be driving under (ambient temps). If I lived in say... Alaska I sure as heck wouldn't run 20w/50. But in Los Angeles where the summers are HOT (not to mention severe traffic) and winters are mild-warm 20w-50 would be fine.

Those that have excessive oil pressure at running temp using 20w-50 if running a stock oil pump have issues elsewhere. If it's built right and within spec one should not see excess pressure when using a 20w-50 if he/she chooses to based on their ambient temp need.

Now let's talk about all the flickering oil lights from those running that thin a PI___! oil they call 30w. Leave the thin stuff for the rice burners. Not to say there wouldn't be a time for it. Just that most don't need it unless the temps go low enough. Just as the manuals call for.


Last edited by udidwht on Sat Jun 02, 2012 8:36 pm; edited 1 time in total
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PostPosted: Sat Jun 02, 2012 5:54 am    Post subject: Reply with quote

Choose oil wieght based on operating temperatures in the engine(and of course mechanical condition). You may find the " thin as piss" oil works perfectly. Good pressure, great running temps, and none of the light flickering. At least in my experience with these engines and oil weights.
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PostPosted: Sat Jun 02, 2012 8:15 am    Post subject: Reply with quote

Well let's see....the ambient air temp here yesterday was 118*, so I know a little bit about driving in hot temps. I base my choice of oil weight on my engines temps both head and oil/pressure not air temps.
I use 10/30 and have been for 10 years. I drive a split Westy loaded for camping and tow a small trailer all over the south west, from Yuma AZ to Denver CO and LA to Albuquerque NM.
I'll be camping at BlackStar, attending OCTO in CA next weekend.
Use whatever oil you think is best for your engine.
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Wildthings
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PostPosted: Sat Jun 02, 2012 8:55 am    Post subject: Reply with quote

udidwht wrote:


Those that have excessive oil pressure using 20w-50 if running a stock oil pump have issues elsewhere. If it's built right and within spec one should not see excess pressure when using a 20w-50 if he/she chooses to based on their ambient temp need.


The VW oil cooling system is designed to maintain a certain low viscosity to your oil. It will try to maintain the same viscosity if you run 20w50 as it does if you run 5w30. The way it does this is to not cool the super thick oil so that its viscosity will be the same as the thinner 5w30 oil. If it can not get the viscosity down sufficiently then it will dump the extra oil to the sump, removing even less heat for the engine and plain wasting that expensive pumping energy you are paying $4 a gallon for. Under otherwise identical engine conditions (rpm, load, and ambient) where a 5w30 oil will run at 200°, 20w50 may run at 240° because the system is designed to let 20w50 get hotter and hotter until the viscosity drops to the proper level.

I you are primarily sitting in traffic and your engine speeds are typically in the 1000-2500 range then run 20w50 if you wish, but if you are out pulling the passes at 4000rpm in third then run something thinner.
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PostPosted: Sat Jun 02, 2012 10:17 am    Post subject: Reply with quote

Here is a link to a side-by-side comparison of all the popular oils. This is very helpful and will probably end the quest for a better oil based on the numbers. Note that the Cleaning action of Calcium TBN above 10.0 is not preferred as the lifter bores live a longer life if the TBN is kept below 10. BradPenn TBN numbers are harder to find to I will just tell you they range from 9-10.6 which is still an excellent choice for our engines, in particular, street engines that do need a little more cleaning action than what some of the other oils provide.
http://www.turbodieselregister.com/TDR57_Oil.pdf


For Comparison

http://www.penngrade1.com/Zinc.aspx
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PostPosted: Sat Jun 02, 2012 8:12 pm    Post subject: Reply with quote

Das Dragon wrote:
Well let's see....the ambient air temp here yesterday was 118*, so I know a little bit about driving in hot temps. I base my choice of oil weight on my engines temps both head and oil/pressure not air temps.
I use 10/30 and have been for 10 years. I drive a split Westy loaded for camping and tow a small trailer all over the south west, from Yuma AZ to Denver CO and LA to Albuquerque NM.
I'll be camping at BlackStar, attending OCTO in CA next weekend.
Use whatever oil you think is best for your engine.



It's been proved that oil will NOT aid in lowering cylinder head temps. Oil temps vs heads temps are entirely seperate from one another. Cylinder head temps are driven based upon load on engine. Oil temps can be related to oil grade, timing or even oil filter choice (highly restrictive flow) or just a plain bad engine build/parts compatability.

With regards to the T-4 oil system (stock) it's been my experience that the relief valve does NOT work like a light switch. It's neither on or off. It 'relieves' any excess oil pressure in the system (if any). There will always be an (x) amount of oil being directed thru the oil cooler at ALL times. That amount will be based on a few factors some of which are: oil grade, ambient operating temps/vs oil grade choice, engine operating temp and owner neglect...yes owner neglect. Ever seen an engine that was severly neglected by it's owner?

Jake Raby has even shown that there are no ill effects in using 20w/50 in the Type-4 engine. In fact it's his oil grade of choice.
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Last edited by udidwht on Sat Jun 02, 2012 9:18 pm; edited 2 times in total
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Altema
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PostPosted: Sun Jun 03, 2012 8:08 am    Post subject: Reply with quote

udidwht wrote:
Ever seen an engine that was severly neglected by it's owner?
Yes, dozens of them! And since this is the oil thread, one case that stood out is where I was checking out a Ford Focus and was shocked at the oil condition. I asked the owner if he ever changed the oil, and he said "Yes, I keep adding oil and it leaks out, so it's always getting changed!" Yes, he said that, and to make it worse he works for Ford...

Rolling Eyes


Let's see, his engine had 200k and is on it's deathbed, and similar engine that gets raced frequently has 200k and runs like new...
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PostPosted: Sun Jun 03, 2012 12:00 pm    Post subject: oil use the best Reply with quote

Hmmm never really thought about using diesel oil in my VW. ( with respect to Rotella)

Back in the old days We used Valvoline racing oil. After many tests of all different kinds of oils. We found that all would break down with the exception of 2. They would drain out like water after 3000 miles.

We found that kendall and Castroll would not break down just became dirty. I had many vehicles that I ran this oil in and all were over 300k before I sold them and still didnt need to be rebuilt.


As for the Idea of using diesel oils. Diesel oils are desinged for the blow by from the turbo pressures and high compression. Eventually the oil becomes compromised by the diesel fuel from the blow by to mix in. This is why most diesels have very thin oil fairly quickly. On my diesel (which everything I have is diesel except my 57 bus). I use Castrol tection extra for the same reason as above. Tried all the others and this one doesnt break down as fast.

On my Rabbit diesel with TDI turbo. I use Pentosin 505.1 rated synthetic. to meet the specification of the turbo bearings.
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PostPosted: Sun Jun 03, 2012 12:27 pm    Post subject: Re: oil use the best Reply with quote

farnhamassoc wrote:
Hmmm never really thought about using diesel oil in my VW. ( with respect to Rotella)


Oils such as Rotella are rated for both Diesel and gas engines. This was true of many other oils before the SM/GF-4 oil specifications came out.
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PostPosted: Mon Jun 04, 2012 2:54 am    Post subject: Reply with quote

Altema wrote:
udidwht wrote:
Ever seen an engine that was severly neglected by it's owner?
Yes, dozens of them! And since this is the oil thread, one case that stood out is where I was checking out a Ford Focus and was shocked at the oil condition. I asked the owner if he ever changed the oil, and he said "Yes, I keep adding oil and it leaks out, so it's always getting changed!" Yes, he said that, and to make it worse he works for Ford...

Rolling Eyes


Let's see, his engine had 200k and is on it's deathbed, and similar engine that gets raced frequently has 200k and runs like new...


Last time I checked Ford wasn't making air-cooled vehicles nor have they ever. Besides no one should never compare a water cooled vehicle to an air-cooled when making comparitive suggestions. They are both entirley different beasts.
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PostPosted: Mon Jun 04, 2012 6:25 am    Post subject: Reply with quote

udidwht wrote:
Altema wrote:
udidwht wrote:
Ever seen an engine that was severly neglected by it's owner?
Yes, dozens of them! And since this is the oil thread, one case that stood out is where I was checking out a Ford Focus and was shocked at the oil condition. I asked the owner if he ever changed the oil, and he said "Yes, I keep adding oil and it leaks out, so it's always getting changed!" Yes, he said that, and to make it worse he works for Ford...

Rolling Eyes


Let's see, his engine had 200k and is on it's deathbed, and similar engine that gets raced frequently has 200k and runs like new...


Last time I checked Ford wasn't making air-cooled vehicles nor have they ever. Besides no one should never compare a water cooled vehicle to an air-cooled when making comparitive suggestions. They are both entirley different beasts.


And they are both 4 stroke combustion gasoline engines using oil. The comparison was between a neglected engine and a maintained engine. Running gritty oil with a failed filter is bad for all engines... is it good for air cooled?
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PostPosted: Mon Jun 04, 2012 10:14 am    Post subject: Reply with quote

Altema wrote:
udidwht wrote:
Altema wrote:
udidwht wrote:
Ever seen an engine that was severly neglected by it's owner?
Yes, dozens of them! And since this is the oil thread, one case that stood out is where I was checking out a Ford Focus and was shocked at the oil condition. I asked the owner if he ever changed the oil, and he said "Yes, I keep adding oil and it leaks out, so it's always getting changed!" Yes, he said that, and to make it worse he works for Ford...

Rolling Eyes


Let's see, his engine had 200k and is on it's deathbed, and similar engine that gets raced frequently has 200k and runs like new...


Last time I checked Ford wasn't making air-cooled vehicles nor have they ever. Besides no one should never compare a water cooled vehicle to an air-cooled when making comparitive suggestions. They are both entirley different beasts.


And they are both 4 stroke combustion gasoline engines using oil. The comparison was between a neglected engine and a maintained engine. Running gritty oil with a failed filter is bad for all engines... is it good for air cooled?



Likely the only time one would/should see the oil by-pass the cooler would be when the filter is nearly plugged preventing the cooler from being damaged. Both may be 4 strokes but the tolerance variations vary greatly as do the running temps.
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Wildthings
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PostPosted: Mon Jun 04, 2012 11:33 am    Post subject: Reply with quote

udidwht wrote:
Likely the only time one would/should see the oil by-pass the cooler would be when the filter is nearly plugged preventing the cooler from being damaged. Both may be 4 strokes but the tolerance variations vary greatly as do the running temps.


What is the difference in the tolerance of the journal bearings between engines of like size? Not much if any. Sure big engines with large cranks can get away with looser tolerances, such as maybe .005 or .007 inches, but if the journals are the same size the tolerances are going to be the same.

Since the bypass valve for the cooler is down stream from the oil filter there is no way a clogged oil filter is going to cause oil to bypass the cooler, just doesn't work that way. All a clogged filter should do is cause the bypass valve on the filter housing to open bypassing just the filter. The oil going to the engine will not even be particularly dirty when this happens.

The oil bypasses the cooler when the system pressure gets sufficiently high, if you visualize how a single relief oiling system on a Type 4 engine works then you will see that the cooler bypass is always fully open before the relief ever starts limiting oil pressure by dumping oil. Essentially if the relief is dumping even a smidgen of oil no appreciable oil is passing through the cooler.
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PostPosted: Mon Jun 04, 2012 10:19 pm    Post subject: Reply with quote

Wildthings wrote:
udidwht wrote:
Likely the only time one would/should see the oil by-pass the cooler would be when the filter is nearly plugged preventing the cooler from being damaged. Both may be 4 strokes but the tolerance variations vary greatly as do the running temps.


What is the difference in the tolerance of the journal bearings between engines of like size? Not much if any. Sure big engines with large cranks can get away with looser tolerances, such as maybe .005 or .007 inches, but if the journals are the same size the tolerances are going to be the same.

Since the bypass valve for the cooler is down stream from the oil filter there is no way a clogged oil filter is going to cause oil to bypass the cooler, just doesn't work that way. All a clogged filter should do is cause the bypass valve on the filter housing to open bypassing just the filter. The oil going to the engine will not even be particularly dirty when this happens.

The oil bypasses the cooler when the system pressure gets sufficiently high, if you visualize how a single relief oiling system on a Type 4 engine works then you will see that the cooler bypass is always fully open before the relief ever starts limiting oil pressure by dumping oil. Essentially if the relief is dumping even a smidgen of oil no appreciable oil is passing through the cooler.


It was reference to air-cooled vs water cooled vehicles of today. The expansion rates versus the two vary greatly. Volkswagens run much hotter than today's water cooled counter parts.

1. Re: Oil pressure...catch words 'sufficiently high'. IMHO I've just not run across a situation where using 20w/50 would cause 'sufficiently high' pressure. But then again I don't live in the cold of Alaska either.

2. The relief as I said earlier does not work like a light switch. It relieves pressure within the system. There will always be an (X) amount of oil going thru the cooler as well as the rest of the system to one varying degree or another.
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Wildthings
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PostPosted: Mon Jun 04, 2012 10:41 pm    Post subject: Reply with quote

udidwht wrote:
It was reference to air-cooled vs water cooled vehicles of today. The expansion rates versus the two vary greatly. Volkswagens run much hotter than today's water cooled counter parts.


This would arguably be a reason to run synthetics as they handle heat better. A typical 20w50 dino oil handles heat no better than a typical 10w30 dino oil. Either will toast at the temperatures typically seen in the rocker boxes.


Quote:
2. The relief as I said earlier does not work like a light switch. It relieves pressure within the system. There will always be an (X) amount of oil going thru the cooler as well as the rest of the system to one varying degree or another.


Nope, when the relief valve piston has been pushed down by oil pressure to fully open the bypass port there is virtually no flow through the oil cooler. Zilch, nada, nothing. With the bypass port open the pressure becomes almost the same on both sides of the cooler and without a pressure differential there can be no flow. No it doesn't act as a light switch, but at pressures well below maximum system pressure the bypass will begin opening and less oil will flow through the cooler.
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PostPosted: Mon Jun 04, 2012 11:32 pm    Post subject: Reply with quote

Wildthings wrote:
udidwht wrote:
It was reference to air-cooled vs water cooled vehicles of today. The expansion rates versus the two vary greatly. Volkswagens run much hotter than today's water cooled counter parts.


This would arguably be a reason to run synthetics as they handle heat better. A typical 20w50 dino oil handles heat no better than a typical 10w30 dino oil. Either will toast at the temperatures typically seen in the rocker boxes.


Quote:
2. The relief as I said earlier does not work like a light switch. It relieves pressure within the system. There will always be an (X) amount of oil going thru the cooler as well as the rest of the system to one varying degree or another.


Nope, when the relief valve piston has been pushed down by oil pressure to fully open the bypass port there is virtually no flow through the oil cooler. Zilch, nada, nothing. With the bypass port open the pressure becomes almost the same on both sides of the cooler and without a pressure differential there can be no flow. No it doesn't act as a light switch, but at pressures well below maximum system pressure the bypass will begin opening and less oil will flow through the cooler.


Your last sentence essentially states what I previously said. The relief gradually opens depending on what pressure is in the system. It's basically spring loaded. You stated , 'less oil will flow...there's a big difference between less an no oil. The relief valve would have to be depressed completely before there is no flow at all. That won't happen using 20w/50 in say...Southern California. If it did one better look elsewhere for an issue. If your racing and looking to squeeze every ounce of power from the motor than definitely don't run 20w50. There are differences between early and late T-4 models as well...single vs double relief valve/s. Or should I say relief valve and a control valve. I believe it was the hydros that had the control valve removed.

Colin quote:

"The Type 4 engine has the same relief valve where all VW engines have it, left rear corner big screw looking thing.
The Type 1 control valve is located at the front left with another big screw looking thing.
The Type 4 control valve for all non-hydraulic lifter engines is located over on the right side between the #1 pushrods, sticking out horizontally and uses a 12-pt allen head to loosen.
The Type 4 hydraulic engines deleted it because hydraulic lifters bleed off excess oil pressure very nicely all by themselves.

Control valves only moderate the upper limit of pump output AFTER the bearings have had their fill. This allowed VW to design-in some excess capacity so these engines could have an extended lifespan before the idle idiot light flicker spells old age. The entire youth of the engine has that control valve dumping oil back into the sump. As the bearings wear, it finally only trims the high rpm stuff and eventually does not get triggered at all.

Meanwhile, every morning, no matter the age of the engine, the relief valve is doing its oil cooler bypassing job because of thick cold oil.
See, it doesn't know about any old worn bearings. Being entirely upstream of the bearings, it's relief dump into the sump is strictly pump output against the resistance of the cooler and the relief spring before the galleries."

End quote


As said, excessively high oil pressure (cold) would/should be the only instance the oil cooler gets by-passed. During normal operating temperature the pressure should not be excessively high enough to dump oil into the sump...unless of course your running thick oil on a cold Alaska morning. A 20w/50 weight oil will behave like a 20w when cold, that is...until it's too cold.
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96mm Biral AA P/C's~7.8:1CR
Headflow Masters New AMC 42x36mm heads w/Porsche swivel adjusters
71mm Stroke
73 Web Cam w/Web solids
Dual 40mm IDF Webers - LM-2 - 47.5 idles/125 mains/190 air corr./F11 tubes/28mm Vents - Float height 10.45mm/Drop 32mm
Bosch SVDA w/Pertronix module (7.5 initial 28 total @ 3400rpm)
Bosch W8CC plugs
Pertronix Flamethrower 40K coil
S&S 4-1 w/Walker QP 17862
3 rib 002 Trans
185R14 Hankook tires
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PostPosted: Tue Jun 05, 2012 7:10 am    Post subject: Reply with quote

Nothing was deleted on the single relief Type 4 engines, both functions were just combined into one valve. As I said on a single relief case the cooler has to be in full bypass before any oil is relieved. By the time that excess oil begins to be relieved there is essentially zero flow through the cooler. The function of dual relief cases is essentially the same, but not quite as clear cut. Do note that on a dual relief case the bypass valve is upstream from the galleys while the dump valve is near the end of the oil stream in one of the lifter galleys. Even if both valves opened at the same pressure, which they do not, the dump valve would open later than the bypass valve due to pressure losses in the system.

It is pretty simplistic to say that the dump valve is only there to make up for having excess capacity in the oiling system. It is there to protect the cooler, oil pump, oil pressure switch, and filter (if equipped) from seeing excess pressure no matter the level of bearing wear.

Running needlessly thick oil causes zero or reduced flow through the cooler until much higher oil temperatures at comparable engine speeds, that is just how it works. If you look at oil viscosity graphs then you will see that a 50wt oil has about the same viscosity at 250°F as a 30wt oil does at 212°F, so 20w50 may be running ~40° hotter at the same engine speeds and loads. The VW system regulates the oil temperature to get the low viscosity the engine needs at higher engine speeds, and when you go to needlessly thick oil it has to raise the oil temperature that much more to get the thin oil it needs for proper lubrication.
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PostPosted: Fri Jun 08, 2012 5:39 pm    Post subject: Reply with quote

In relation to some stuff posted above, I thought I would post that I just changed the oil in my 36hp from Castrol 20W/50 to the Shell Rotella 15W-40 I have been using in my other Bus.

Pretty much the same temperature outside before and after the change and using my IR thermometer in the same position on the generator stand after a highway run of 10 miles gave me a 10F-degree drop in case (oil) temp.

(It was actually more than 10F but I'm giving it some degree of error and saying 10F so think of it as 10F minimum).

Anyway, take it how you will but some real-world data is always nice...

No fancy oil pressure or oil temp. gauges though.
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PostPosted: Fri Jun 08, 2012 8:39 pm    Post subject: Reply with quote

Main thing I have against thick oil is that if it doesn't circulate through the engine as much as a thinner oil, it's not going to pick up as much heat. Some have said they noticed a temp drop with the thick stuff, and attribute it to the superior film strength creating less friction, or whatever. My contention is the friction is still there, it's just that the oil isn't removing as much of it. I'd rather have the thinner oil passing through a cooler to carry the heat away from critical parts, it just seems like a better idea.
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