Track Day Excessive Oil Temp for factory recommended 0w-20 persists

[ZDan]

Originally Posted by dowroa

@Frost, then are you matching the viscosity charts of your oil at 270 to the spec that Subaru has for the tolerances of the FA24 (and I am not sure if RPM is dictated in this spec)?

Engines designed to run over a *very* wide range of operating temps can handle a *very* wide range of oil viscosity.

Pretty likely that Subaru and/or Toyota have repeatedly tested this engine to redline (oil temp goes up with revs) with factory fill 0w20.

Still, for repeated track usage, with oil temps at 270-275F, IMO it's a good idea to run 30 weight at least. The manual even mentions running higher viscosity for sustained high temperature environment and/or usage.

Again, viscosity of 5w30 at 275F is about the same as 0w20 at 250F.

I know this is a topic older than time, and I am more than happy to look into this more but I am not aware if general users are given the specifics to make a claim that 270*F is OK with Oil-X at weight Aw-B to maintain an appropriate film with C-hours and a max of D thermal cycles of the oil.

As far as that goes, neither does anyone have specifics to make that claim at 250*F either...

When in doubt, why not run cooler and conservative? Then the problem is no longer a min/max or limits issue?

Throwing additional parts + oil lines + connections = points of failure at a problem that doesn't really exist, may not *really* be the "conservative" approach...

For track-dedicated cars that see much longer stints (full races or endurance), yeah, you might want to run a cooler, if just for some additional margin so you can tolerate more and not have to back off in a race, particularly if being in traffic affects cooling airflow.

My car is my daily-driver and sees usage in sub-freezing winter months. Even with a thermostat, these cars with aftermarket added-on oil coolers likely won't get oil up to temp ever for those months. Not good...
And for me, on track I'm never in a lot of traffic (if I find myself in a "train" it's no biggie to just pull in and drive down pit road), my oil temp never tries to "run away" on me during the stints I run.

For *me*, the more conservative approach is to just run 5w30 at ~272F and not worry about running an oil cooler.

[Frost]

Originally Posted by dowroa

@Frost, gotcha sir.

Also, if I was an automotive engineer that isn't designing this as a track car, I think there are some assumptions the user isn't driving WoT for 20 mins as a time. I am not sure they design or test to that specification.

With that stated, thermostats are a good thing. Pressure drop is a real thing. Agree with understanding your variables, concerns and data before just `doing a thing`.

Thanks for your insight.

There's an iterative process I'm sure. Size the cooler for the biggest band of customers that DOESN'T overheat when exposed to track use within reason and DOESN'T overcool for most markets.

[NoHaveMSG]

Reading this thread reminds me I really need to get my test setup working and logging correctly.

[Frost]

Originally Posted by NoHaveMSG

Reading this thread reminds me I really need to get my test setup working and logging correctly.

Knowledge is power!

Not horsepower but it can lead to it!

[NoHaveMSG]

Originally Posted by Frost

Knowledge is power!

Not horsepower but it can lead to it!

If I can get the damn thing logging and communicating correctly it would answer a lot of questions.

[zeroomega]

I just want to point out Toyota factory backed 86 Cup racecar suggests to use 10w60 oil with oil cooler. I bet they know what they are doing. I won't 10w60 since I still drive my car on the street occasionally, 10w60 would require a lot of time for warming up. But it also means Toyota racing engineers know 0w20 is not suitable for long time racing and oil temperature will be an issue.

For me, I prefer to set up my car with more margins. The oil can definitely withstand over 270F without disintegration, but making the engine running under normal temperature will likely to reduce the chance of breaking it. An used FA20 engine costs a lot nowadays due to the stupid valve spring recall. I run Jackracing's dual radiator/oil cooler to increase cooling capacity of both oil and engine coolant and it can keep the oil temperature below 240F under 110F ambient temperature when driving hard on track for 30mins. Is that good enough? I don't know. But without the oil cooler, the oil temperature will probably reach 270F and engine will start to cut timing (which is also bad for lap times). There have been a lot of 86 race cars have spun rod bearing issues in racing applications due to oil starvation if you search the ft86 forum. In my local area, one of the 86drive challenge racers's recently has engine replaced due to spun rod bearing in cylinder 3. The car did have oil cooler and running 5w30 oil. But it's a 2013 model with valve spring recall so it might be related to the poor recall work. The car logged over 40 track days after the recall. This type of issues are so common on ft86 cars. If lowering the oil temperature and increase oil weight a bit can help lower the chance of engine breakages, I guess you should do it.

[DocWalt]

Originally Posted by Tokay444

So that I have fresh oil for daily driving.
Depending on how old the oil is, I've even changed it before and after a track day or two.
Heat cycles are not the oil measure of an oil's integrity.

I'm just... not going to bother.

[OkieSnuffBox]

Originally Posted by ZDan

For *me*, the more conservative approach is to just run 5w30 at ~272F and not worry about running an oil cooler.

Yep, the car doesn't even go into limp mode until the oil is right 300° IIRC.

My Mustang GT was the same.

[DarkSunrise]

Originally Posted by Tokay444

How much does your new oil cooler restrict flow? I bet no one knows that answer.

Setrab publishes this data for their oil coolers online. It’s pretty easy to find. It’s not an industry secret or anything.

[WolfpackS2k]

Originally Posted by OkieSnuffBox

Not really. Look at the oil temps any modern performance cars run ON THE STREET.

The thermostat for the stock oil on my 135 wasn't even set to open until 240 degrees. And routinely ran 245-250 just in street driving.

Modern engines run much higher temps because they are more efficient at making power and produce less emissions. This is why you don't see people putting in lower temp thermostats for the radiator like the did in cars up until the early 2000s.

Seems like this. My C63 runs 220+° just cruising down the freeway with cruise control on. I had it on Tail of the Dragon this past weekend and in mid 80 degree weather the oil temp gauge indicated 275° roughly 8 miles into an uphill run. This engine seems to run hot. Prob why everyone runs high temp LiquiMoly in them.

[timurrrr]

Originally Posted by Frost

There are disadvantages of running oil too cold (which I'm in an environment where it can legitamately happen).

Thermostat?

Originally Posted by ZDan

My car is my daily-driver and sees usage in sub-freezing winter months. Even with a thermostat, these cars with aftermarket added-on oil coolers likely won't get oil up to temp ever for those months. Not good...

Have you tried though?
I didn't notice much change in how quickly the oil warms up at ~0ºC temperatures after installing an oil cooler with a thermostat (Jackson Racing Dual Oil Cooler / Radiator).
Have you tried using thinner oils for winter? 0w-20 or 0w-30?

[ZDan]

Originally Posted by zeroomega

I just want to point out Toyota factory backed 86 Cup racecar suggests to use 10w60 oil with oil cooler.

I woulda thought 40- or 50-weight should be about ideal for track-only usage at 270F. 10w60 at (probably?) 250F temps? Seems kinda thicc...

For me, with 90%/10% street/track, and track sessions usually ~15 minutes, I run 5w30, might consider 5w40 next year (just ordered Redline 5w30 which will cover me for last couple of track events this year).

I run Jackracing's dual radiator/oil cooler to increase cooling capacity of both oil and engine coolant and it can keep the oil temperature below 240F under 110F ambient temperature when driving hard on track for 30mins. Is that good enough? I don't know. But without the oil cooler, the oil temperature will probably reach 270F and engine will start to cut timing (which is also bad for lap times).

For sure you'll hit 270F, I get there around 3-4 laps in.

There have been a lot of 86 race cars have spun rod bearing issues in racing applications due to oil starvation if you search the ft86 forum. In my local area, one of the 86drive challenge racers's recently has engine replaced due to spun rod bearing in cylinder 3. The car did have oil cooler and running 5w30 oil. But it's a 2013 model with valve spring recall so it might be related to the poor recall work.

I've searched this a lot. Yeah, there are oiling issues but IMO not related to temperature so much as to pickup tube and design of the flow through the engine. And almost always, if there's a spun bearing, it's a 2013...

The car logged over 40 track days after the recall. This type of issues are so common on ft86 cars. If lowering the oil temperature and increase oil weight a bit can help lower the chance of engine breakages, I guess you should do it.

But as you say, even *with* an oil cooler, these failures happen. Again, IMO more related to tortuous and inefficient flow paths... Thicker oil with good HTHS will help a bit, but ultimately if the oil isn't reliably being delivered to the bearings, there's likely gonna be tears sooner or later

[ZDan]

Originally Posted by timurrrr

Thermostat?
Have you tried though?
I didn't notice much change in how quickly the oil warms up at ~0ºC temperatures after installing an oil cooler with a thermostat (Jackson Racing Dual Oil Cooler / Radiator).
Have you tried using thinner oils for winter? 0w-20 or 0w-30?

I run 0w20 in the winter.
I've seen more than one thread about oil with an oil cooler and thermostat never getting up to temp. Also that one Savagegoose guy, he went to trouble to install a cooler, then his oil wouldn't heat up enough in winter so he removed it, and after he reinstalled it started leaking...
I believe most setups ensure there's always *some* flow through the cooler even with thermostat closed so the oil in there gets cycled around and heated up regularly.

[timurrrr]

Originally Posted by ZDan

Also that one Savagegoose guy, he went to trouble to install a cooler, then his oil wouldn't heat up enough in winter [...]
I believe most setups ensure there's always *some* flow through the cooler even with thermostat closed so the oil in there gets cycled around and heated up regularly.

Curious if "just block off the airflow with a piece of cardboard" is too ghetto of a solution to this problem.