Elasto,
Oil coolers are a great idea, and no matter what, I wouldn't run any moderately powered engine without one.
But you're describing an abstract technicality, that specifically 'cooler' oil can take more heat before reaching it's breakdown point. No one can argue that. I mean, that's like Obama's "Change" slogan. Yeah, sure, 'change' is inevitable, regardless of whether he exists or not.
Change isn't always good or as promised.
Oil coolers don't generally cool oil any lower than NOT. They nominally stabilize oil temperatures@ around NOT when more heat is input into the bulk oil. The oil itself still has to be able to complete it's journey unscathed; perform under the heat and pressure in the first place before it can get back to it's 'safe haven' to be 'reborn' if you will.
I don't think stepping out of a meat freezer vs a sauna is going to make much of a difference if I subsequently jumped into an active volcano- my fragile meat-robot would get incinerated either way, even if they returned my corpse to the freezer (with a toe tag etc). Case in point? Mammals are unsuitable for volcanoes.
Likewise, all this compensation for using the AN INCORRECT VISCOSITY FOR THE APPLICATION is NOT going to give 0w20 any more durability in service, it'll still GOING to be abused by supercharged, high-RPM 4 cylinder duty; a fantastically different condition than a Prius ICE.
Originally Posted By: Shannow
Given that the replacement rate of the
oil in the ring belt is of the order of 10s of seconds to minutes (I posted a link to a paper a few weeks ago), I can't see a cooler materially altering the ring belt/cylinder wall temperatures
Good point, that's like an eternity @ 400degrees