It is difficult for anyone to evaluate different oils effectively - but these engines have the potential to suddenly give rise to temperature hot spots (due to various reaction system times, faults and failures). Under normal operating temperatures - if temperatures were equal with a small temperature rise throughout the engine then most high quality oils of the right viscosity range would work well - but it is if and when a sudden hot spot occurs that problems can follow".
To which the response was - "Surely more regular oil/filter changes to maintain quality lubrication is also worth doing?"
This is like answering the question of if God exists? with "well God says" etc - the response does not relate to the question completely objectively.
I cannot see any connection with what I was quoted as saying about the general position and any suggestion I would promote reducing oil change intervals and of course changing the oil regularly is better - the more often the better too - unless you are getting silly about it. Indeed due to the particles that gradually filter into the oil - and the degredation of additives and the base oil - the high quality oils often only preserve that performance longer than cheaper ones that might be just as good if changed more often.
I have not mentioned this to promote a new argument but just to demonstrate how the reaction to the question about oil choice often has little to do with the original question I answered and really seems to be just posted to demonstrate that the poster knows more about the subject and I am wrong (just like with how to bring up your child, religion or politics) it seems to be taken beyond a normal reasonable discussion to a conflict.
I am not a tribology expert and I think it would be wrong of me to argue on the subject - all I can do (and have) is reproduce what our oil suppliers have explained to me and leave it to the readers to decide what to do.
As I understand it a thinner high quality oil will transfer heat better than a thicker oil (due to anti shear) providing the additives maintain the oil film - but I am not an expert although our results suggest the advantages explained to us were proven.
Another point raised was that "Molybdenum disulphide granules in this specific oil does lub well but there are reports of it blocking oil filters towards the end of a 15k/2year service interval(which Porsche approve on the 997 for example). This is in the form a light sludge that coats engine parts. Owners sticking to the 2 year 18k mile service interval may be creating issues for themselves by using nano technology vs those who change engine oil far more regularly with no sludging issues. Clearly a race car gets many oil changes and many have enhanced engine cooling, so issues with nano technology may never occur......but on a road car with a 2 year service interval?? "
Can I point out that at Hartech we do not recommend 2 year oil changes and (for example) on our Lifetime Maintenance Plan the maximum we allow between changes is 1 year or 12K - despite the fact that for a fixed price maintenance scheme this obviously costs us far more than if we adopted the Porsche recommendations (and we will change at 6K intervals if requested depending on the age and mileage of the particular scheme) so to imply we do not agree with frequent oil changes is completely the opposite of our clear position and totally misleading
.
Another argument raised was in response to my comment "I therefore look at it as a kind of failsafe in these rather delicate engines" and was as follows.
"Surely if you have raced these engines(as outlined below) at max revs, meeting after meeting then stripping them down with no issues the word "delicate" is perhaps a tad misleading? In fact, I would suggest that it speaks volumes about the general quality and reliability of the Porsche 911 engine"
My response is that the above comment is utter nonsense and it is not because our engine designs and components are bullet proof that they have lasted well in racing - but because of our skill at assembling them, and other measures we took (all allowable) to improve reliability plus the limits we placed on the maximum revs and ignition and fuelling (which we are allowed to change).
Compared to a 993, GT3 or Turbo there are many components in a Boxster S or 996 that have been manufactured cheaper but with less high quality - that result in the general reliability being lower and will result in them being unable to cover the same mileage without rebuilds.
Furthermore - the basic crankshaft design compared to those other models - incorporates a long overhang at the rear end that allows more crankshaft flex and reduces rear main bearing life.
The Open Deck cylinder design also reduces the rigidity of the cylinder roundness and leads to early cracking and piston blow by (compared to those other models that do not incorporate those features).
This is why so many engines are being rebuilt - so what are we arguing about? DOES THIS NOT MAKE THEN RATHER DELICATE?
These issues mean that the engines will not be as reliable for track use or long term high performance aggresive driving. The Boxster S has lower output and piston weight with basically the same engine as a 996 and so does last better but the larger the engine the less strong they are and the shorter their lifespan will be.
Then I said that "So far (touch wood) in one and a half season of racing with several engines) we have experienced no engine failures of any kind during the Porsche Club Championship (which we are leading\) and have only experienced one failure in another event with a driver unfamiliar with the car (not connected in any way to normal racing but due to external influences beyond the engine's control).
We have just stripped three of them for rebuilds before the last 4 race meetings that involve 9 races (as they are all crammed into just 6 weeks), without finding any problems needing attention - fingers crossed - racing always throws up the unexpected and we all live in hope that we can continue with this excellent record - but know anything can happen!"
To which the response was ".....as can engine failures on BMW, VW, SEAT's etc of course but its always encouraging to read about such fantastic reliability reports from a Porsche race team who are working these engines very hard indeed." To which my response is - YES it is encouraging to see that some specialists can overcome the basic weaknesses and get reliability at racing speeds despite them.
These are actually the different engine designs to most Porsche racing engines and I don't think Porsche have raced the M96 or M97 engine range (although I stand to be corrected) - certainly the majority of their own race engines (and the vast majority of those raced for years Worldwide are quite different) and have features, components or design changes that make them more suitable..
I think a reasonable person can see from all this that my simple attempt to offer a low key sensible response to a direct question was broadened out to an argument largely nothing to do with the question and quite misguided in the links and points made that were more posted to start an argument or elevate the status of the post provider than to help answer the question that was anyway directed to us.
Consequently I am not going to waste any more time nit picking over the bones previous or no doubt to follow and hope those requesting my advice understand why and will allow me to decline any more on this subject.
As I already knew before (and should have paid more attention to) it seems that "OIL" is just one of those taboo subjects that generates responses that are too intense and argumentative to justify too considered a response.
Baz.
