Oil Cooling - An In-Depth Look

[weederr33]

Originally Posted by Semiihcircle

My oil gets really hot when on the highway cruising above 3500 rpmAttachment 181375

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Woah, wtf. Why is it so hot? Even before I had the Forester exchanger on, it didn't get anywhere near that in the dead of summer.

[Dzmitry]

Originally Posted by weederr33

Woah, wtf. Why is it so hot? Even before I had the Forester exchanger on, it didn't get anywhere near that in the dead of summer.

Actually, that is quite normal. Cruising at speeds of 70-80 mph, my oil temperature centers right between the 190-270 mark (Around 230F). His looks slightly higher due to sustaining higher RPM's. This is a topic I recently brought up in another thread and am curious myself if running at 230F for periods of an hour often times is something for me to consider in long term engine wear. I plan on keeping my car for as long as I can, and I DD it somewhat, so I am trying to determine if a Forester heat exchanger is necessary or if these temps are not significant enough to cause any excess wear running on 0W-20.

The thread that I began this discussion at recently starting on post #108:
https://www.ft86club.com/forums/show...t=91820&page=8

Also, here are some good reads on the topic of oil and research on brands:
https://www.minimania.com/Motor_Oils..._Misunderstood (Informative of the basics and misunderstandings of oil. Loads of good information).
https://www.ilma.org/PDF/ILMANews/2017/AAAreport.pdf (Not really related to these topics, but just goes to show that there is no reason to be using conventional oil anymore for all new car applications).
https://dextrous-lubricant.com/amsoil/PDF/g3115.pdf (Probably posted a few times somewhere around this thread or others, but some interesting information on brand comparisons).

[tehShirt]

Originally Posted by weederr33

Woah, wtf. Why is it so hot? Even before I had the Forester exchanger on, it didn't get anywhere near that in the dead of summer.

I had a 2 hour road trip cruising around 70-75 mph on the highway and my oil was around those temps. Anytime I'm on the highway it gets up there, I assume it's due to the elevated RPM when cruising above 60 mph.

[weederr33]

Originally Posted by tehShirt

I had a 2 hour road trip cruising around 70-75 mph on the highway and my oil was around those temps. Anytime I'm on the highway it gets up there, I assume it's due to the elevated RPM when cruising above 60 mph.

I've seen mine climb up to about 225-230 on long 2-3hr drives but that's about it now that I have the oil regulator on. But I normally don't go above 75mph for long cruises anyway. The way their gauge looked made it seem much higher.

[celicanegrita]

Hi there,
Anybody using the Forrester OEM solution to keep the oil on the right mark can share some experiences? I have to do something with my oil temp because in the spirited mountain roads the oil reaches 130ºC (270F) and I have to slow dow to cool it...somo of you are recommending the Forrester solution because it is enough while others think that this solution is more oriented to warm the oil faster on winter days. The other way to go it is an oil cooler...but maybe this is not really needed. Any help or comment wil be appreciated!!!!

[Grady]

Originally Posted by celicanegrita

Hi there,
Anybody using the Forrester OEM solution to keep the oil on the right mark can share some experiences? I have to do something with my oil temp because in the spirited mountain roads the oil reaches 130ºC (270F) and I have to slow dow to cool it...somo of you are recommending the Forrester solution because it is enough while others think that this solution is more oriented to warm the oil faster on winter days. The other way to go it is an oil cooler...but maybe this is not really needed. Any help or comment wil be appreciated!!!!

For what you are doing the Forrester OEM solution should work. As far as heating/cooling is concerned its a thermal dynamics thing.... If the oil is colder than the coolant it will warm it, If the oil is hotter than the coolant it will cool it.

[celicanegrita]

Originally Posted by Grady

For what you are doing the Forrester OEM solution should work. As far as heating/cooling is concerned its a thermal dynamics thing.... If the oil is colder than the coolant it will warm it, If the oil is hotter than the coolant it will cool it.

First, thank you Grady for you comments...I wonder if I am plannig some autocross sessions or some racetracks occasionally, the forrester solution will be enough too...because that is really the purpose of having a BRZ in my case.

[Grady]

Originally Posted by celicanegrita

First, thank you Grady for you comments...I wonder if I am plannig some autocross sessions or some racetracks occasionally, the forrester solution will be enough too...because that is really the purpose of having a BRZ in my case.

For NA, I would say Autocross no problem, Track good unless you are going to be doing over 20 min sessions.

[celicanegrita]

Originally Posted by Grady

For NA, I would say Autocross no problem, Track good unless you are going to be doing over 20 min sessions.

Ok, I understand....thanx!

[AngelGT86Racer]

I have the Forester/WRX cooler routed through the throttle body.


For mountain/spirited canyon driving, I see peaks of ~232 F.
Autocross runs that are a minute long or less, I can't even get the oil up to operating temp (212 F).


Track, I don't believe it's enough cooling. On a 75 F ambient day, I see peak temps as high as 251 F. The temp itself isn't catastrophic for the oil if it's a quality oil. My concern is with how much my oil pressure tapers at high rpm when I hit those temps.


I don't plan to track my car again until I get a more serious cooler - something with an external radiator that will keep oil temp <240 F for 20 min sessions.

[celicanegrita]

Originally Posted by AngelGT86Racer

I have the Forester/WRX cooler routed through the throttle body.


For mountain/spirited canyon driving, I see peaks of ~232 F.
Autocross runs that are a minute long or less, I can't even get the oil up to operating temp (212 F).


Track, I don't believe it's enough cooling. On a 75 F ambient day, I see peak temps as high as 251 F. The temp itself isn't catastrophic for the oil if it's a quality oil. My concern is with how much my oil pressure tapers at high rpm when I hit those temps.


I don't plan to track my car again until I get a more serious cooler - something with an external radiator that will keep oil temp <240 F for 20 min sessions.

I see...that's why I am not sure if I should be going for the Forrester cooler and spend the money is something that will not be enough...or save the money and buy a real oil cooler...


The Forrester cooler kit will cost me around 250€ and the Mitshmoto thermostatic oil cooler around 500€...

[86MLR]

If I was going to do the twins again I would still go O2W, namely a JR

https://jacksonracing.com/product/fr...toroil-cooler/

[celicanegrita]

Originally Posted by 86MLR

If I was going to do the twins again I would still go O2W, namely a JR

https://jacksonracing.com/product/fr...toroil-cooler/

Ummm...interesting solution, but I would not like to change the OEM radiator...thanks any way for this original alterntive.

[ZDan]

Originally Posted by celicanegrita

I have to do something with my oil temp because in the spirited mountain roads the oil reaches 130ºC (270F) and I have to slow dow to cool it...

Wow, I never see anything like that on the street...

At the track, I get to ~272F indicated and it holds there. Even in 95F ambient temps. Do you feel your oil temp would "run away" if you didn't slow to cool down?

Good synthetic can handle 270F oil temps, much higher even, but I would recommend running 5w30 weight or maybe even 5w40 to keep viscosity at elevated temp.

Originally Posted by AngelGT86Racer

I have the Forester/WRX cooler routed through the throttle body.
...
Track, I don't believe it's enough cooling. On a 75 F ambient day, I see peak temps as high as 251 F. The temp itself isn't catastrophic for the oil if it's a quality oil. My concern is with how much my oil pressure tapers at high rpm when I hit those temps.

251F I wouldn't worry. Run 5w30 and viscosity should be similar to 0w20 at 220F.

I'm running 272F every session, usually 15 minutes duration. I don't feel the need to run an oil cooler. I do run 5w30 oil, might consider 5w40.

Regarding pressure at elevated rpm, there's a good thread on this suggesting a larger-diameter aftermarket pickup tube improves this. I'm considering that before tracking this year. I don't have any plans to run an oil cooler for my usage...