Pennzoil confirms CaSa contributes to LSPI, maybe.

[wemay]

This SAE study has been dicussed at length before...
http://papers.sae.org/2014-32-0092/


But now, through Pennzoil's Q & A, the topic came up again and they have answered it this way. Remember, SOPUS oils are rather laden with CaSa...

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3836844/Pennzoil_Answers-Complete_Prot

Q: Could you address operators of GDI-Turbo vehicles regarding the effects of certain additives such as calcium and their impact on LSPI (low speed pre-ignition)? There's much discussion and concern by operators of these vehicles that Pennzoil's additive packages are predisposed to LSPI as compared to other brands.

A: Low speed pre-ignition (LSPI) is more a phenomenon of engine design – and as you mentioned, occurs more frequently in gasoline direct injection (GDI) turbocharged engines. It is really a phenomenon for prototype or experimental engines that are still in the Research & Development phase, and oils with high levels of calcium-based detergents can increase LSPI frequency. HOWEVER, by the time the engine is fully designed and released to the market, it must be compatible with the available motor oils in the marketplace. Thus said, there is no need for concern.

 

[Garak]

Yes, but the manufacturer decides what specifications, among the oils available in the marketplace, would be chosen to be compatible with the engine. Ask for an E7, E9 specification, and you're probably going to get a magnesium package, for instance.

 

[wemay]

Originally Posted By: Garak
Yes, but the manufacturer decides what specifications, among the oils available in the marketplace, would be chosen to be compatible with the engine. Ask for an E7, E9 specification, and you're probably going to get a magnesium package, for instance.


Yes, i agree but would Calcium have any bearing on what certifications or approvals any product gets? If yes, that would be interesting. But i'm not sure there is any correlation.

 

[Garak]

No, not really, aside from an E7, E9 mostly being found with magnesium, and I suspect it helps them get SA at 1 or less while keeping TBN nice and high. A calcium package won't be getting in the way of SN/GF-5 certification or any of the basic OEM certifications we see in North American makes, and is probably more common than any of the others in that regard.

 

[wemay]

 

[CT8]

What about zinc and moly or any of the other adds?

 

[Virtus_Probi]

It would really stink if somebody found that magnesium compounds are a potential problem in DIT engines, too.
I guess if that were true, I might shell out for M1 ESP 5W30 with its low calcium, close to zero magnesium, and low TBN, but just make sure to change it often. Although its -30C viscosity from VOAs is not very attractive to me, about 5000 IIRC.

 

[Garak]

You likely won't be testing MRV or CCS limits anyhow. Nonetheless, I can imagine some people might be peeved about using such a lube on short OCIs, at least with us not having ULSG yet.

 

[weasley]

Originally Posted By: Garak
No, not really, aside from an E7, E9 mostly being found with magnesium, and I suspect it helps them get SA at 1 or less while keeping TBN nice and high.


Do you mean E6 and E9? Either way, it is perfectly possible to get both with calcium-based packages.

As a principle, rarely do specifications limit specific chemistry unless it has specific issues with hardware (for example phosphorus with cats, zinc with silver plating etc).

That said there are more and more collaborations between engine and oil manufacturers at the design stage to get the ultimate benefits of a bespoke, made-to-measure oil. I suspect though that rather than excluding specific elements in specifications, OEMs will simply introduce engine tests that probe an oil's capability to prevent certain issues and will only approve those that pass.

 

[Garak]

E6 applies, too, but we do have E7, E9 lubricants that have the magnesium package. Notably, the Delvac 1 ESP 5w-40 I'm using is E7, E9 and has the magnesium package. Delvac 1 LE 5w-30 is E6, E7, E9. I don't know what it's additive package looks like, but if I was forced to make a guess, I'd say magnesium as well.

And you're right, it is certainly possible with a calcium package. But, magnesium might give them a little more leeway. The VOAs I've seen over the past couple years with E7, E9 lubricants have shown them switching to magnesium, even where they were calcium before.