The reason for my apprehension is this: there is a whole lot more going on with oil and the engine/oil interactions than can be fully described by the information available to us as consumers.
For that matter, there is more going on than is fully understood by the oil manufacturers and blenders. That’s why in addition to laboratory tests, API and ACEA approval also requires a battery of engine tests. It’s also why manufacturers’ have established their own tests and approval programs above and beyond API and ACEA standards.
The standards themselves also evolve over time. Take a look for example at the API engine testing to determine the high-speed/high-ambient-temperature performance has evolved over time:
• Sequence IIIE (ASTM D 5533) used in API SJ – this is a 68 hour test run on a 1986 GM V-6 engine at an output of 67.8 bhp
• Sequence IIIF (ASTM D 6984) used in API SL – this is an 80 test run on a 1996/1997 GM V-6 engine at an output of 100 bhp
• Sequence IIIG (ASTM D 7320) used in API SM –this is a 100 hour test run on a 1996/1997 GM V-6 engine at an output of 125 bhp
From this evolution of test requirements, we can infer a few things; (1) what’s going to happen under those conditions remains enough of a mystery that the test must be run to find out; (2) even with a long history of testing, what’s going to happen remains enough of a mystery that the tests performed to find out are continually being improved; (3) you can’t accurately extrapolate results on one engine under one set of conditions to another engine and another set of conditions, i.e. you can’t entirely predict the results of the IIIG test from the IIIF or IIIE test results. Even with these limitations however, the important thing is that the oil has been specifically tested with acceptable results.
As I mentioned many posts back, I don’t believe API, ACEA, or manufacturer approvals represent the holy grail of engine oil performance. But the smart money plays the odds, and your odds are better with an oil that has been vetted by one or more independent agencies. While it’s not a 100% guarantee of performance, it is a significantly less uncertain proposition than using an oil for which these tests have not been conducted or for which the results are unknown. Exactly how much significance one places upon that uncertainty is pretty much an individual choice, there is no single right or wrong answer.
Regarding Redline in particular, one specific concern is the very high level of moly in their oil, about 4~5 times that of almost any other oil (Motul 300V being one known exception). The effects of moly in oil seems to be a subject without clear consensus. Some claim remarkable benefits, some assert remarkable harm. Both may in fact be correct, depending upon exactly what conditions, what engines, what moly levels, and what type of moly are being talked about. What does inspire skepticism though, is that there does seem to be consensus amongst the majors about what’s an appropriate level of moly. These companies spend employ a lot of talent and a phenomenal amount of time, money, and effort developing oils. If the secret to making a super-oil was a simple as dumping in more moly, they’d be doing it too. The reasonable inference is that nothing comes without side-effects and more is not necessarily better. Oil chemistry is all about balance and trade-offs. In comparison with other oils, the Redline moly levels seem out of balance. That may in fact be a reasonable trade-off, but in the absence of detailed information, such as that implied by API or ACEA approval, there’s simply not enough information to tell.
Finally, back to your question of what I’d run in my car at the track. With an M52TU engine, I’d shoot for something at the heavier end of the scale like a 5W-40. I haven’t checked out price or availability on any of these, but here’s a list of possibilities, in no particular order.
• Havoline Synthetic 5W40
• Liqui Moly Synthoil High Tech 5W40
• Penzoil Platinum European Formula 5W40
• Q European Formula 5W40
• Mobil 1 5W40 or 0W40
• Titan Supersyn (SL) 5W40
• Shell Helix Ultra 5W40 or 0W40
• Motul 8100 X-cess 5W40 or E-tech 0W40
All of these oils have formal API, ACEA, MB, BMW, and Porsche approvals. I have yet to hear of anything any of the “boutique” oils have to offer sufficiently above and beyond the properties these oils that would justify to me accepting the uncertainty that comes with lack of approvals. To put it another way, with several high quality choices that do carry approvals, why bother using something that doesn’t?
What you want to use in your car on the track is entirely up to you. I’ve looked in to the issue in regards to my car and my needs and done my best to explain the reasoning that underlies my choices. You’ve got a very different car and engine than I do and quite possibly a different outlook on what is an acceptable risk. So it’s perfectly reasonable for you to consider the information available and make a different choice.
