DER951

The info in this thread has been great. Many thanks to 67King for the detailed write ups.

Based on this, I bought Motul 300V, and planned to change it after 500 miles. Then it was posted that it is good for 3000 track miles, more than enough for my DE season, unless there's a time element. My season is from late April thought mid October, and will involve no more than 2000 miles. Is the Motul 300V good for 6 months after first use? Car is trailered to track.

hacker-pschorr

Gotcha - no worries
I'm here to learn too!!

So does Mobile 1

So that leaves us with three conclusions:

1. Valvoline and Mobile 1 are lying on their data sheets.
2. The API ratings are meaningless
3. The people that put that page together on aa1car.com are misinformed.

I'm leaing towards #3 as the most likely scenario. Especially since I've seen multiple oil analysis from the VR1 and Mobil 1 that support the rated ZDDP levels.

Are all GF-5 oils SN? As far as I've been able to find, yes.

Are all SN oils GT-5? No

I'm just as confused as you are by all of this. I honestly think it has something to do with viscosity. GF-5 only covers the thinner oils while SN doesn’t have that limitation. Every SN oil without a GF-5 stamp is a higher viscosity oil.

Or this spreadsheet from Mobil1.com I'm now posting for the third time in this thread

http://www.mobil.com/USA-English/Mot...duct_Guide.pdf

67King

Here we go. I dug through and found out. The ASTM D4951 provies for a maximum allowable amount of phosphorous not to exceed 800ppm. But it only applies to 10W30 and thinner oils. However, it applies to ALL "energy conservation" oils. http://www.api.org/certifications/en...l1complete.pdf Note phosphorous comes from ZDDP and in the case of ester, some of the base chemicals used to form the oil (I think acids).

hacker-pschorr

Perfect!! Who says nothing ever gets solved in this forum?

chrisc

Agreed! Now that is solved - Gasoline, is Sunoco better than Chevron or is Quicktrip ok or should I use Shell, or Texaco, but my friend who drives a gas hauler told me Kroger is really Chevron.......

Nick Wong

Hmm...

Thanks for the info. I understand your PoV concerning marketing vs. engineers, been there many times myself. In my specific case concerning my car/engine, they were quite specific that factory fill was more than adequate although they did of course add the caveat that changes were preferable after sustained hard efforts at the track.

How about some general data concerning Group III vs Group IV or V breakdown vs. temperature exposure? Perhaps a graph illustrating your point to show under what circumstances a Group IV or V based oil is superior?

al@cpt

I was looking for a viscosity vs. temperature chart and found this site. Looks like good info with references:
http://www.bobistheoilguy.com/puttin...nto-viscosity/

67King

Let me see what I can dig up. Been pretty busy the past couple of days, sorry if I can't get it right away.

chrisc

Surprised but just got a call from Mobil regarding a question I posted on their site. It was suggested I consider using Mobil 1 Racing 0W-50 in my 924S (944) motor for racing applications. The zinc content is 1900 PPM's and the Phosphorus is 1750 PPM's. The caller said the 0 package is tested at 35 below F vs the 15 package that is tested at 25 below F, which they say will have no effect in the temps where I operate the car. They also responded to my question re usiing the V-twin stuff and they said again they would use the Racing 0W - 50 oil. Interesting.

Sterling Doc

Did they say what made the racing oil better then the V-Twin stuff?

chrisc

They sent me this catalog -
http://www.mobil1racing.com/pdf/2012_Catalog_V2.pdf

Sterling Doc

Thanks, Chris, that was interesting.

The 20/50 V-twin description does include this statement:

It looks like the main difference is the lack of friction modifiers in the motocycle oils - might give up some HP to the racing oils.

chrisc

Think it also mentions the V-Twin oil is good for air cooled Porsches