Steve Weiner-Rennsport Systems

Yessir,.....having been at this in various forms since 1963, I've learned the value of using certain lubricants during engine assembly and initial brake-in. Further, initial engine start is VERY critical for camshaft/rocker arm break-in and we strictly follow procedures to prevent problems. I learned about the value of ZDDP way back in my V8 days,.....

We use a break-in oil containing additional ZDDP for initial engine start and the first few hours on the dyno to prevent flat cams and damaged rockers.

IMHO, flat tappet and SOHC with rocker arms require engine oils with Zn & P levels of 1200ppm to ensure these parts will last 100K+ (provided proper oil change intervals are used). Too much isn't good either so one must choose wisely.

The vast majority of engines with bad cams that I've seen since 2002 either suffered obstructed spray bars or used oils with ZDDP content less than 1000ppm.

Glenn Evans

I believe that the answer may lie in the mandated maximum sulphur content. While ILSAC GF-5 and API SN specify that the phosphorus content be from 0.06 to 0.08 per cent by mass, GF-5 limits sulphur content to 0.05 per cent for 0W-XX and 5W-XX oils, and 0.06 per cent for 10W-XX oils. I have yet to find the detailed specificaton for API SN, but suspect that the sulphur content will be similarly low.

The ZDDP family of compounds have one zinc, two phosphorus and four sulphur atoms in every molecule. The atomic weights of these elements are 65.38, 30.97 and 32.06 respectively, therefore their masses in ZDDP will be in the proportions 1.056 Zn:1 P:2.07 S.

If the sulphur content in oil is limited to 0.06 per cent by mass, then the maximum proportion of zinc which can be present in the oil in ZDDP is only about 0.03 per cent.

No wonder Steve is still seeing discrepancies between wear and zinc content.

http://www.swri.org/4org/d08/gastests/ilsacGF5.pdf

Glenn Evans

No, that's not necessarily the answer. API SM limited phosphorus and sulphur only for viscosity grades 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30. API SN does so for these grades and if the oil is labelled "Resource Conserving" (the API Donut). For these oils, however, the ZDDP content will be in the order of half what might be assumed from the phosphorus content.

http://www.api.org/certifications/en...l1complete.pdf

Steve Weiner-Rennsport Systems

Hi Glenn,

While the API appeared not to specify nor regulate 15w-40, 15w-50 & 20w-50 engine oils, our VOA's have found ZDDP levels lower than what manufacturers advertised and claimed in their literature. For that reason, we test a few products that we use to confirm sufficient levels of Zn and P for proper engine protection.

My advice to anyone curious about this subject would be to have VOA's (its not expensive) done on whatever oils they may be considering to ensure the maker is honest. After all,......the bottom line is that its your engine and they will not bear any liability for anything that may happen.

Glenn Evans

Thanks for that, Steve!

For several years now, I've only used oil for which the Zn and P content is published, as I am not willing to accept any company's glossy brochure which claims good anti-wear properties but doesn't divulge Zn and P contents. . I belong to a car club which runs navigation rallies, primarily for cars over 30 years old, and the magazine has just reprinted an "Oil is Killing Our Cars" article highlighting the importance of ZDDP. The article doesn't help owners here in Australia select suitable oils, but I will suggest that we get UOAs on some new oils and share the results.

(I guess VOA is Virgin Oil Analysis? I just realised that that probably wasn't a typo!)

ble2011

Ok. I've been following this thread to make sure I'm doing the right thing using Mobil 1 15/50. Unfortunately for me, some of these posts are getting way over my head. I recently asked PCA about Mobil 1, specifically 15/50 weight. They emailed me back that I should be using Mobil 1 0/40 or 0/50. I posted this question on this forum and people here have stated that they are incorrect. I respect a lot of people here so I'm going with the folks on this forum. But, I'm still confused and I guess I will continue using Mobil 1 15/50 as my 993 seems to be running great and not burning any oil. But now I read that I need to validate Mobil's spec sheets by getting a "VOC" done to confirm what they are saying is in their oil? Man, does an oil change really need to be this difficult?

Slow Guy

In post #1 I've edited it to add the latest M1 Prod. Guide (dated 10/17/2011).

Steve Weiner-Rennsport Systems

JMHO,.........

I would never trust ANYONE at an oil company for any kind of recommendation. It sounds like they may not understand the differences between an air-cooled and water-cooled engine (based on their advice) as their oil requirements are quite different.

Talk to the people who actually work on these cars and repair/rebuild these engines for good recommendations about products. After all, these are the folks who are on the "front lines" and deal with all the consequences every day.

Its not difficult at all,........just choose your "guru" and follow their advice to the letter.

Glenn Evans

ble2011,

Car manufacturers and oil companies will not risk being branded anti-environment by admitting that anything other than low viscosity, low phosphorous, low sulphur oils are best for your engine. Most mechanics don't realise that changed oil specifications are to blame for the wear that they now see. Even if they do, they don't want to risk being sued if they blame the oil. We are fortunate to have guys like Steve Weiner, Charles Navarro and others who are willing to give us the benefit of their observations and expertise.

Oil companies do not divulge the amount of ZDDP in their oils. Not all (almost none in Australia) will divulge their oils' zinc and phosphouous contents. Steve recommends a zinc content of 1200ppm (0.12 per cent by weight) to get enough ZDDP, but not all zinc in new oil is necessarily present as ZDDP.

Steve has observed discrepancies between the claimed zinc levels for some oils and the wear he has seen in engines run on those oils. That is why he has the oils he uses tested, and has recommended that anyone using a different oil to those he recommends has it tested to verify the ZDDP levels if they want to be sure that the oil will adequately protect their engine.

Note that oil companies may change the specification of their oils without notice, and that formulations may be different for different markets eg Mobil 1 15W-50 sold in the USA and Australia is not necessarily the same.

FlatSix911

Bill, thanks for posting the updated M-1 product guide.

I have used oil analysis on my car and here are the updated recommendations:
1200 ppm ZDP is the minimum number for Porsche air and oil cooled engines

There is one street oil and four race formulated oil types that meet that criteria:

• 15w-50 Mobil 1 for Street applications (see chart)
• Mobil Racing and Mobil V-Twin for Track applications (not for catalyst cars)

Viperbob1

Have been using the Mobil 1 0w-50 Racing since it came out a little over a year ago. We run it in the race cars, and several guys decided to use it in their street cars. No ill effects so far.

FlatSix911

Hey Bob, long time no see in Los Altos ... how is life in Tampa?
The only downside to running the M-1 racing oil in a street car is the reduced life expectancy of the catalyst ...

Viperbob1

Hi Ted. Yeah miss Los Altos... Tampa not quite the same.

Yeah using the racing in a street car was not my idea. But will be interested to see what if anything happens. Cars are driven a fair amount.

Glenn Evans

I am curious why there is a need for a 0W-50 oil for racing. After all, cold starts aren't a big part of a race oil's life. I understand that monogrades are still used by many racers in different categories to avoid high temperature shear of viscosity improvers. I suspect that it's a high ZDDP oil which Mobil can claim is not for the street!

When the Dyson team came second and fourth in the 12 Hours of Sebring in 2008, I e-mailed them to ask what Mobil oil they used. The answer was 0W-40. There was no commercially available M1 0W-40 Racing at the time, but they didn't say whether it was the same as the oil sold for street cars.

Slow Guy

The latest (April 2013) version.

Link

I will also attach the file.