code5coupe

Not BS at all, my friend. Your car leaking oil has nothing whatsoever to do with the performance of the oil in the crankcase.



That post pretty much wraps up the question of Mobil 1's suitability. They only thing most of us will "notice" is a leaky engine (or an engine that doesn't leak). Will we notice better/worse bearing protection? Will we notice more/less corrosion protection? Will we notice more/less heat resistance? No....because we can't. We don't have the means to test various oils for all these things.
We can only see spots on the garage floor, or a clean floor.

These are old cars, men. As someone has already said; don't blame the oil if your engine can't keep the oil inside itself. Performance, in the context of this forum, is not something we can measure. Too many times we form opinions based on what we hear others say.
Will Brand X oil perform "better" than Brand Y? It could be, but your engine will never know the difference.

code5coupe

I need to point out some things.
1) Oil doesn't drain away from bearing surfaces, at least not all of it. If it did, engines would not last for more than about 5 cold-starts. A film of oil stays on the cylinder walls, cam lobes, other bearing surfaces for many months (perhaps years) of idleness.

2) It would have to be mighty cold for 20 weight oil to thicken to the consistency of honey. 20W-50 oil IS 20 weight oil, after all. It's a 20 weight formulated for Winter use (that's where the W in 20W comes from). I doubt if anyone on this forum even tries to fire up their car when it becomes cold enough to thicken 20W-50 to honey-like viscosity.

Forums are full of urban legends/old wives tales/misinformation. Be careful. (Shoot, don't even believe me...)
Oh, yeah, another place where a little skepticism will serve you well is believing what you read on a company's website when it comes to descriptions of their product. Fully expect them to paint those products in the most glowing and complimentary terms that the advertising people can devise.
When an oil company says they are the only one in the world to use a certain base stock, I find myself thinking "If it's so good, I wonder why no other company will touch it."
Something to think about.

ZPmadA

What needs to be done to switch from dino oil to synthetic? I've heard the two dont mix well and you need to be very careful to drain all the dino before filling with synthetic? For what its worth, I drained my 20w50 today and it overshot the drain pan, I got oil on the floor. Didn't act very "honey like" to me... ofcourse I did drive it, but I let it cool off before draining so I wouldnt burn myself, and yea I did read in the owners manual the 20W is winter, and the 50 is when things get hot... Multi-Viscosity oils are all season oils, its not like i'm running single Viscosity 50 weight oil. Anyone use Pennzoil Conventional, the stuff in the yellow bottle? Autozone has a sale this week, original price is equal to the Valvoline racing so i'm guessing they are about the same quality? I'm noticing condensation on my oil cap so I want to experiment with different oils and see if that'll change anything? I'm not loosing any coolant so its not any of those issues.

Charlie944

A Engine Flush treatment would be advised before switching to a synthetic. Add this to your existing dino oil. Should change your filter too to catch the particles that the engine flush dislodges (can be a cheapo filter due to the 15 min of use). DO NOT drive the car with flush treatment in with the oil. Just let it sit at a fast idle for 15 minutes.
Look here for more info:
https://www.amsoil.com/storefront/aef.aspx

jimbo1111

I hear that 20/50 robs horse power. The heavier oil hitting the crank could affect performance.
I am thinking about going to 0/40 mobil 1. I recently used it in my atv and could swear that the motor quieted down by a good 20%. Can we use 0/40 in the 951?

Charlie944

Depends if you are considering 20w-50 parrafin (dino) oils or synthetics. Synthetic oil is more uniform in molecular structure and provides less resistance to flow therefore in order to achieve the same flow volume as a petroleum oil, which has a higher frictional resistance to flow, it is possible that under some conditions, such as idling that a slightly lower oil pressure could be noticed, but that the oil flow volume delivered to the engine is adequate for the engine operating RPM and conditions. Synthetic oil has better flow characteristics than petroleum oil and may also cause an engines RPM at idle to increase due to decreased resistance to flow, less internal drag and parasitic losses.

The beauty of it is that a 20w-50 Syn has greater film strength yet can flow much easier with less drag, and less friction.

I have heard and IMHO that with our older design engines (1/2 a 928 engine) and the 928 engine development started in the 60's that we should user thicker oils. If you had a new Carrera or GT-3 the 0w-40 would be the recommended choice due to their tighter tolerances.

A lower viscosity weight oil could be used for short sprint distances or it is more officially called a "qualifying viscosity" but for endurance situations I would choose a higher viscosity.
Check out what Redline has to say about their 0w-10 and 5w-20 race oils:
http://www.redlineoil.com/products_m...46&subcatID=15

DFASTEST951

Jimbo1111, how funny you bring up the 0/40. I just talked to David at Powerhaus Racing. I was talking to him about oil. He said he will be putting the 0/40 in his car as ALL factory porsches are now supplied with 0/40 from the factory. On a side note. He became a distributor of Royal Purple and the very first engine he built blew up with very low miles on it. He never thought it may be the oil until he talked to a few racers who had the same exact problem so now it's AGIP or he said Castrol 20/50 which is what my car was broken in on.

ENGINEERMAN

When I stated that the oil does drain away from the bearing surfaces over time this was not based on urban legends it was based on 25 years of compressor and engine design experience. No it does not completely drain away over night but it is a fact that a cold start is when you have the greatest likelyhood of metal on metal contact, PARTICULARLY when the engine has been idle for an extended period of time.

Now I live in Minnesota and believe me in late October it gets cold here and 20w-50 gets very thick at 32°F. I am not trying to start an argument with you over this but I am not just repeating things I have heard, I actually work in the field and have worked with the oil company experts to understand the physics behind what is going on.

I spoke with Dave Lindsey about this and they never use synthetic oil in their cars. They use 20w-50 Dino. They said they for some reason noticed that they had higher lifter wear with synthetics. It doesn't make sense to me. Since all of the anti wear properties are better with synthetic. The numbers are very much in the favor of synthetics. For a relatively inexpensive synthetic Castrol Syntec 5w-50 has excellent VI, Flash Point, ash & Zinc content numbers.

ehall

Unless you are running an NHRA drag car, where a thousandth of a second is life and death, the hp consideration of the oil viscosity shouldn't even enter into your mind. Even on a full race car, it shouldn't matter at all, because so many other things will determine your success or failure, not the least of which is blowing up the engine. If you're that worried, pull your back seat, and the rear wiper, and run thicker oil.

lleroyb

ehall, did you say you could find a Porsche document that would clarify the 952 designation?

UK952, I believe as you say, I would like to convince someone else of the same.

I spoke to a formula V driver, they blended their oil to get a custom viscosity to save horsepower. They run a ragged line between protection and power. I agree this should not be a consideration in a 951. You can't win a race you don't finish.

Lou

Zero10

Say what? The W means winter?
20W50 is a 20 weight?!
Wait, down really is up!
I'd really like to see a reference for this information.

At -5*C, 20W50 was about as thick as honey, maybe a little thicker. I know because I tried to drain my oil when it was that cold. Of course this was before removing one piston, so I had to remove the pan anyways. Once I removed the pan, I was able to mop about 0.5L more oil out of the pan. It was seriously thick.

I drove my 951 with Mobil 1 10W30 right down to -19*C. So, there are some of us who drive our cars well below the point where 20W50 is as thick as honey.

LFA951

Amsoil 20W50 Series 2000 Racing Oil year round here in Florida, anything less is too thin, changed every 5,000 miles...

turbinek

Have you got oil stocks?
You race your car?
How can you tell anything else is too thin? Have you been involved in the engine design process?

Unfortunately Porsche has simply not really a recommandation what charakteristics it must match; that was I unterstand from the part in the owner's book.

Jay Gratton

I carry and sell Amsoil and it is my most popular and best selling line! I can't keep it in stock! I have seen engines taken apart that have had Mobil 1 used and then engines taken apart using Amsoil. Everytime the engine with Amsoil looks MUCH better! Mobil 1 is different in the USA then what Porsche puts in their car for Mobile 1 in the europe. Thanks everyone - Jay

streckfu's

No it doesn't.

at code5....