Another thing to point out is that all drivers and track days are not the same. I drive my car in the upper RPM range and manage my shifts to keep the RPMs 5k-7200 ALL THE TIME. That takes some practice.
An HPDE 1-2 driver is not going to do that, so that will have an effect on the outcome. I just don't want to hear some HPDE 1 Boss driver come back and say the non-standard, unrecommended oil WORKS FINE on track. Because its a ticking time bomb.
Any smart Boss track driver won't be doing this, so we likely won't have good data points.
And I've decided to send my oil out for analysis after the recommended FOUR HOURS of track use (high RPM track use). I will post the findings here.
Ticking time bomb? You use Motorcraft 5W-50, yet call any true synthetic 10W-40 use on the track a ticking tomb bomb?
Post up your UOA after 4 hours of high RPM track use, let's see how rapidly it sheared. I'd love to see it.
Question, if it shears to a 40 grade lubricant within your testing parameters, what does that mean to you?
Sorry, but i'm not following you on this. The oil that's recommended doesn't impact the cost of producing the car (ok, it does, but very minimally), so why would the bean counters care? If we take it one step further, if the oil recommended wasn't good enough to sustain the car (including some track use....since that's what the car was designed for), they might also face higher costs for warranty claims....aka engine failures. No?
Or perhaps the oil is just good enough to get through the warranty period....and then they can reap the benefit of having more $$ generated through engine repairs the owners have to pay for? <----Have a hard time believing Ford would take this approach with the Boss.
I'll take my chances with the Mobil 1 5W-50.
To clarify, engineers do not always get final word in a decision process. For example, a reliability testing engineer with the 4.6L 3 valve engine, after 100 tear down tests, noticed Motorcraft 5W-30 was performing better in the engine than Motorcraft 5W-20. Wear was reduced. However, the bean counters feared fines from the Federal Government for CAFE laws, deciding on the 5W-20 recommendation anyway. Why you ask, because 5W-20 still allowed this engine to perform far outside the warranty period and the slight increase in fuel economy would reduce CAFE fines. This is not saying that a premium 5W-20 lubricant in a grocery getting grandma driving Mustang would not achieve 300k+ miles. It's simply more towards the performance junkie. This engineer recommended Ford stick with the Motorcraft 5W-30 requirement, or equivalent. Upper management didn't agree.
That doesn't make any sense at all. I understand in your data that the MC shears rapidly. Are you saying if you change the MC 5w50 per the manual for track use that HT/HS doesn't matter?
Er...not sure where you're getting that data, but pretty sure that's not quite right either. The specific heat of oil is not different with different viscosities. Perhaps you mean to say they generate less heat?
And are you saying that less viscous lubricants have a higher average viscosity in extreme conditions? Is that a typo?
No, I simply meant that the lubricant would likely shear outside of the grade during the first or second weekend of use. HT/HS would no longer be in the 4.9-5.0 range a 50 grade lubricant provides. True synthetic 10W-40 lubricants hold in the 4.3 range. 30 grade lubricants drop to the 2.9-3.1 range. Motorcraft 5W-50 HT/HS is estimate to be in the 3.5 range after 1,500 miles of use. cSt @ 100*C averages in the 13.x range after this many miles.
Also, a lighter lubricant releases heat more rapidly than a more viscous lubricant. This will REDUCE your oil sump temps, therefore allowing the less viscous lubricant to maintain a higher HT/HS rating on average than a more viscous lubricant. In easy terms, Amsoil 10W-40 would maintain it's HT/HS raiting at the high end of it's average. The more viscous Motorcraft 5W-50 would maintain it's rating at the lower end of its average. This would allow their HT/HS ratings to be closer than what actually shows on the specification sheet.
I still don't get why you've recommended the 10W-40 in the past to anybody even doing one track day. I've seen a handful of Boss guys say they're running the 10W-40 after reading your threads and were planning on doing from one to a few track days. Since I haven't seen a UOA from a Boss using 10W-40 and *any* track miles I've been a little concerned for those guys.
Most Boss track owners are terrified of doing anything other than what Ford says, despite science. I've chatted with racing experts before, and their knowledge is vast.....right up until you try to discuss lubrication technology. The extent of their knowledge is....."I use this because XYZ said I have too." or "I use this because it's what I am sponsored with."
IIRC, just the bearings, rod bolts and maybe a couple other things. While almost everything will cross-bolt between the two, they are more different than alike.
Bingo, bearing clearances. Translation, on the street....5W-50 is NOT required. You can use Ford's recommended 5W-20 if you wanted too, since the high levels of heat common on closed course will not be present. All local Boss 302 cars in my area, street use only, are rocking Amsoil ATM 10W-30. The engine starts easier, get's better efficiency & power output, and wear decreased.
and to all those who think "Automotive company engineers know best, I always listen to them first". Do you really think they are always right and have the best solution for a design? If that were the case, this would not be happening to the 5th generation Camaro. Sometimes, they have to work with what they have, not what they wanted or asked for. (i.e. Motorcraft 5W-50)
Video and article link
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