rnl

Well, I'm getting older and cranky.

RennListUser01

Wait - to the OP, please keep asking questions - I haven't seen a new oil thread successfully make it recently!

Porsche_nuts

rnl - you see what I mean.

rnl

Yup

IXLR8

You mean this oil thread where Lake recommends against using Mobil 0W-40 European Car Formula due to a high level of Calcium.

Lake also brings up an article about LSPI - Low Speed Pre Ignition.
https://www.pera.org/low-speed-pre-i...on-phenomenon/

From my take on watching the lengthy 1h 30 minute video, it seems to me that LSPI issue applies more to high torque at low rpm engines, in other words recent "turbo" engines.

Also, if this LSPI is such an issue, why are Porsche engines not being replaced in large numbers? In fact I have not heard of any and if so, what percentage?

I'd also like to know what a "Certified Lubrication Specialist" is. Is that a degree or PhD you get from some university?

Wayne Smith

There have been many articles. What you have watched is good, IMHO. You definitely are showing initiative and interest!!!! Kudos 😀

LSPI can occur at 2500 rpm. In other words, highway cruising speeds. There is a school of thought that says we should never operate under 2K rpm because this can be abusive. This is based on loads created given the bore and stroke geometry on our motors creating excessive side thrust. I believe this is more of a problem for M9X motors through 2008 than the 9A1 motor. The 9A1 doesn't seem to mind low rpm operation. And the ECU is very good at adjusting timing to minimize knock. But the adjustment is after the fact. And many who know more than me (very many!!!) feel LSPI is a real concern.

Preignition overloads the rod bearings (journals) which doesn't matter if you're only keeping the car for a few years. But if you're looking at going a quarter million miles then this may be more of a concern for you. I have seen pictures of the 9A1 motor pulled apart with flattened journals, so I believe this problem is (eventually) real.

Elmiko

I sometimes wonder if it’s possible that there really aren't that many refiners/blenders each with its own special formula but instead they’re all pretty much the same because they come from the 2 or 3 largest oil companies?

Wayne Smith

It's like gas. Each company adds their own formula. But for oil the bases do vary.

However, for specific qualifications, like A40, there are fairly strict rules on what those additive packages are.

See ...

https://www.k2-global.com/blog/class...20W50%2C%20W60).

While we are used to seeing A40 as the oil we should use, for DFI check out the C20 here ...

https://www.blauparts.com/blog/porsc...oil%20standard.

IXLR8

Comes from being inquisitive and asking myself questions when I don't agree with what is taken as gospel, and of course going to college and working in labs.

What I thought and came up with some years ago when I was reading about bore scoring out of interest. But the experts with an interest in the subject came up with other reasons for the issue.

My previous daily driver that is now in the hands of a friend with 205,000+ miles on it and it still runs like day one. Of course I looked after it for most of those miles. By the way, his 2005 997.1 has 112,000+ trouble-free miles on it. When looking at pictures showing disasterous images of failed engine parts on the internet, like that pic a few posts up, it is much like media sensationalization and good at putting the fear of God into owners. Sure it can happen, but then you really need to get the whole story. And if LSPI is such an issue, we'd be replacing engines left and right and there would be some class action lawsuit.

spdracerut

It can also be an engine tune/calibration issue along with an engine's particular fuel spray pattern in the cylinder paired with bore size. The Ford 2.3l ecoboost was notorious for blowing up due to LSPI. So Porsche's fundamental engine design along with differences in calibration could be the difference.

IXLR8

Might be. Glad you brought this up because it got me digging for info on oil manufacturer's web sites.

As I mentioned before, it seems LSPI is most noticable on smaller turbo engines and direct injection where at low RPM the driver punches the throttle in his turbo generating high cylinder pressures.

I also came across this on the Castrol web site: Provides superior protection in gasoline direct injection engines (including but not limited to GDI, FSI, SIDI, Eco Boost – check your owner’s manual for details).

Also: "Once researchers started digging into why these events were happening, they found that a detergent used commonly in engine oil, calcium sulfonate, was reactive to the conditions of LSPI. Testing reduced calcium sulfonate in engine, they noticed that LSPI events were significantly curbed".

Note that API came out with the "API SN Plus" rating in May 2018. Is this listed in Porsche Owner's Manuals since then, and if not, then it may not be an issue.

SinkRate

For what it's worth, I've run nothing but Pento in a B8 Audi S4 for the last 10 years and 140,000 miles. It's good oil*












*based on my personal observations of it going in clean, coming out dirty, never having a single issue with the engine, and it generally just not exploding.

IRunalot

Honestly I think we are splitting hairs on high end oils and change intervals are important. The DI40 stopped the cold start lifter knock so I was happy but I'm sure it would be just fine having the oil changed at the dealer. I'm not losing sleep over any of this to be honest.

RennListUser01

IRun,

What do you attribute the improved cold start lifter knock to? Higher or lower viscosity? Different additives? (if so I wonder why all oil manufacturers don't simply add these same additives).

I always thought this as simply a matter of how the lifters responded to viscosity vs component temperature - and, whether the lifters are solid or hydraulic.

Wayne Smith

To qualify as A40 certified things have to be added to the base oil at certain ratios. That ties the manufacturers' hands. Therefore, most A40 oils are pretty much the same.

At the start of a new motor design, engineers test and guess on the best oil. As motors develop miles and get torn down for wear analysis, oil problems start to show up. In the past few years, engineers have changed the 9A1 (or to split hairs, the 9A2) recommended oil type due to realizing problems with the amount of calcium in A40 oil for DFI motors. This was Porsche saying the A40 oil wasn't working as well as they would have hoped, and LSPI damage was significant enough to cause them concern. So the A40 recommendation was retired.

And yes, Porsche suggests different oil requirements for different cars. Look at the "oil / learn more section" of this link to realize how many different types of oil are recommended for different models ...

https://www.porsche.com/usa/accessor...rts/engineoil/

Also, refer to the attached picture.

Designer oils have the advantage of being able to make their own formula. Thus, they can remove calcium to avoid LSPI, which has been recognized as a problem, whether we see it in mass during the brief interval most own these cars, or not.

You can go designer, or now you can change to the newer oil recommendation, or you can stay with the engineers' original guess. In any case, you'll most likely be fine.

As for lifter noise at start up, I don't know. The more common start up noise on the 9A1 motor is chain noise which diminishes as the hydraulically tensioned guides develop pressure. It could be the DI40 is quicker to pump those guides up. Or maybe the different oil doesn't drain from the tensioner as quickly.

Modern oils are very good. Does one brand make a big difference over another? Define big. Are you worried about start up noise? Do flattened journals concern you? Do you do UOAs to evaluate wear and optimal change intervals? Do you want to keep your car for 250K miles or more? Most would say no, no, no, and no. And in that case, you're not apt to see any difference between any of these oils. And all of this discussion is then simply mental gymnastics.