Need Some Help Deciphering a Blackstone Lab Report

[spendy]

Originally Posted by Chuck W.

I did my yearly oil change on January 1st and sent off a sample to Blackstone Lab for an oil report. I changed last year from 13 years of Mobil One to Joe Gibbs DT40.

Looking at the report I noted that the magnesium is at 130 whereas the highest previous reading was 24. What do you think? Engine issue or new oil?

I've had a couple of blackstone reports done on DT40 in my '98 boxster SPB. Both of them showed magnesium around 150. Based on this, I'd say your change is due to the oil. Also interesting to note that my reports have shown low viscosity (10.4 & 10.8). I see yours are better than mine, but at the low end of spec.

[steved0x]

My magnesium on my last UOA was 127 with DT40 vs 21 with Castrol Edge 5W40, and that was with the first change so there are still traces of the Castrol in there. Could be a DT40 thing.

I am hoping the Silicon goes down when I get the next one done, it is not my air filter, I think when I dropped the sump before the oil change that is the subject of the most recent UOA and cleaned out the snakes of silicon from the previous owner having the valve cover "gasket" replaced I must have stirred up some silicon or else added some when I sealed the sump cover.

[Perfectlap]

Originally Posted by spendy

I've had a couple of blackstone reports done on DT40 in my '98 boxster SPB. Both of them showed magnesium around 150. Based on this, I'd say your change is due to the oil. Also interesting to note that my reports have shown low viscosity (10.4 & 10.8). I see yours are better than mine, but at the low end of spec.

I might be mistaken, but I thought you weren't supposed to track the car with DT40?

[spendy]

The story on that has changed over the years. The Gibbs web site still shows it as a track day oil, but I'm looking for something else. Not many ?w40 choices out there..

Originally Posted by Perfectlap

I might be mistaken, but I thought you weren't supposed to track the car with DT40?

[steved0x]

Originally Posted by spendy

The story on that has changed over the years. The Gibbs web site still shows it as a track day oil, but I'm looking for something else. Not many ?w40 choices out there..

I've seen that too. I talked with Lake Speed Jr. and he felt that DT40 was an appropriate choice for me, in the green instructed PCA DE group type of sessions.

[Gelbster]

The UOA from Cat or anyone else won't tell you if the oil film is breaking down because of foaming. Foaming is a physical issue ,not chemical. That is why foaming is so difficult to understand and requires both mechanical knowledge of the M96 and tribology to adjust the foaming with additives. Real dry sump flat engines don't have this issue -sigh.
If an M96 fails due to a lubrication problem, how would you know if the cause was lack of shear strength in the oil or just foaming of otherwise 'good' oil? As a foam, oil has negligible shear strength but an unaerated sample of that same oil could show acceptable shear strength.
I suppose you could insert a borescope-camera above the oil level in the sump immediately after engine shut down ?
Alternatively just choose an oil with 'plenty' of silicone and a bare minimum of detergent ? Hopefully people like Lake Speed and Jake will get a well funded R&D contract from a generous oil sponsor to figure it out ! Without such tests to define specific levels in the additive package, it is all mere conjecture to mutter about silicone and detergent.Mea Culpa.