odurandina

"Synthetic oils can be made to achieve multi-weight ratings *(without viscosity modifiers that break down after just a few hundred miles) that would be impossible without lab production. This is important for exotic cars and German automobiles that require a very low viscosity during starting and a high viscosity during normal operation. Examples of this are 0w40 and 5w40 oils."






and the oil that won the ALMS.....

$12.99/qt

http://www.nissanraceshop.com/produc...Fao7OgodHjwALQ


.

Dino V

Good deal.

mikey_audiogeek

Porsche require a HT/HS value of >3.5 - that's why in the Mobil 1 spec sheet they refer to "Porsche applications".

A lot of the 10W40 oils are marginal for HT/HS (3.2-3.7) but the 10W60 I use is 5.7...

Just checked the Mobil 1 racing 0W50 and it has a HT/HS of 3.8. Mobil 1 15W50 has a HT/HS of 4.5.

mel_t_vin

And, I stand corrected, as well. It appears the HM oils, indeed, have 1000/1100 ppm P/Zn, as shown in the product guide.

Thanks for posting the actual information.

John_AZ

odurandina,

I have reduced your massive post and shouting to post a reply.

I have read the the report posted by H.F.B.
The report on Motor Oils by Dr. Ali E. Haas, a Venice FL. plastic surgeon, repeated most of your bias.
He has a deep focus on the benefit of "cold oil viscosity" as a primary theory to his paper.

I prefer to get advice from "real" laboratories that test used oil from engines. Used oil analysis "UOA" will report the impurities in the oil--in a specific engine. Collecting the information to make detailed observations after thousands of individual tests.
Blackstone Lab, OCLS-Oil Check Laboratory Services and LN Engineering.

I have already posted another source of information--the engine rebuilders and oils they would use in the 944 series.

The experience of Porsche 924S, 944 series owners on the forums leans to the category of "drivers" and "enthusiasts".

There are many experienced members that meticulously keep the cars in OEM condition and your information may apply.

The information I suggest reading applies for the average 924S, 944 owner.
The information applies to "air cooled" and high performance engines.
Updated 1-18 2012.

Included information is oil change intervals and much more.

From LN Engineering

Http://lnengineering.com/oil.html

J_AZ

jep32

Simply put, VR1 20w-50 year round

odurandina

not trying to argue more about oils, film strength, film strength summer/winter etc...

but i'd like to mention that it has long been my understanding that it was Porsche themselves who added M1 0w40 as anofficial Porsche approved oil for the 944... didn't they?? if my information is inaccurate, please excuse my error....

http://forums.pelicanparts.com/porsc...-approved.html

http://www.lnengineering.com/oil.html

curtisr

I'd like to try Lucas 20w-50 Plus High Performance Oil. From their web site:

The "PLUS" is for an extra additive package above and beyond a normal 20w-50 racing oil.The user can expect high lubricity, lower oil temperature (up to 40° F) and a stronger protective additive film that stands up to racing fuel dilution at least 50% longer than other racing oils. As is with other Lucas oil products, you are assured of 'wet' starts every time. Excellent of course, for normal highway usage. Meets SL standard for ZDDP.
- See more at: http://www.lucasoil.com/products/dis....yqreBlJ5.dpuf

From http://www.aa1car.com/library/api_mo...ifications.htm:

If you are driving an older classic muscle car or hot rod that has an engine with a flat tappet camshaft, you should be aware of the fact that today's SM and SN rated motor oils contain much lower levels of anti-scuff additive called "ZDDP" (Zinc Dialkyl Dithio Phosphate). The level of ZDDP in current motor oils has been reduced to no more than 0.08% phosphorus to extend the life of the catalytic converter. Phosphorus can contaminate the catalyst over time if the engine uses oil, causing an increase in tailpipe emissions.

The lower ZDDP content is not harmful to late model engines with roller lifters or followers because the loads are much lower on the camshaft lobes. But on pushrod engines with flat tappet cams, the level of ZDDP may be inadequate to prevent cam lobe and lifter wear. In some cases, cam failures have occurred in as little as a few thousand miles of driving! This is even more of a risk in engines if stiffer valve springs and/or higher lift rocker arms are used.

To avoid such problems, you should add a ZDDP additive to the crankcase, or use an oil that meets the previous SL service rating, or use diesel motor oil or racing oil that contains adequate levels of ZDDP to protect the camshaft and lifters.

odonnell

Sorry for a potentially stupid questions (they exist).

I've already decided on a 20w50 oil. Is Castrol GTX ok in our cars? I've heard VR1 and Brad Penn around here, but just want to check if I can get something better for my car.

John_AZ

Castrol GTX 20-50 has a little less ZDDP ppm than VR1. It is a fine oil as there is a possibility that added ZDDP is not necessary or has added gains.

The choice of a better oil is the discretion of the owner.

Just make sure to use the OEM or equivalent oil filter with the proper anti drain back valve.

J_AZ

Dougs951S

Castrol GTX is a conventional oil though. I would personally feel better about putting a 15w50 full synthetic into my car (that doesnt leak) vs a slightly thicker conventional. I would think Michael that with your fresh build, you'd be better served running a full synth oil.

odonnell

Hmm, I'll probably order high zinc 15/50 full synthetic then. Thanks. I have a Mahle OC 142 with the proper valve.

Aero426

The Castrol GTX is no longer an oil I would consider using for a car requiring the high ZDDP protection. The VR1 and Brad Penn would be excellent choices. VR1 is easy to buy off the shelf at many locations.