What would improve overall/global cooling more: Oil Cooler or Performance Radiator?

[ddeflyer]

I am working on getting a new oil cooler for my car (stock engine BRZ).

I don't think i've ever seen the coolant temp go over 100 C but on the track (I've watched it at Laguna Seca and Thunderhill) I hit oil temps of about 125 pretty easily (even on cooler days). Also doing pad bed in on the freeway late at night (ie. when no one is around in cool weather, I speed up to ~70 mph and brake hard to 20, rinse repeat a few times) I've seen oil temperatures hit 135.

From everything I've heard that kind of temperature will quickly degrade even the best of oils. Because of this I currently am theorizing that an oil cooler is very much needed and am planning on getting the jackson racing one (I've been told that they will release one with non-FI mounting in time for my next track day).

[fooddude]

Air-to-oil vs water-to-oil coolers?

Is it me..or does it sound like water-to-oil (ie: cusco, oem forester, etc.) cooler are a little redundant and not as effective?

Meaning... aren't all cars with a radiator effectively like a giant "water-to-oil" cooler already? ...especially since all the coolant passes inside the head and block already and is already cooling the same thing - the oil and the block. Wouldn't re-routing the lines be effectively almost the exact same thing as just leaving it bone stock with no water-to-oil cooler? Idk...just the way I see it, Lol. Anyone else think this too, or am I the only one? I can't really see this(a water-to-oil cooler) being much different than stock or being much different without one.

Just sounds a bit gimmicky to me. And, if you think a forester having a similar water-to-oil cooler as oem means it's not a gimmick; then why didn't they put it on all subaru models? Maybe subaru saw that it didn't really work, so they didn't put it on their other models.

[Model Citizen]

Originally Posted by fooddude

Air-to-oil vs water-to-oil coolers?

Is it me..or does it sound like water-to-oil (ie: cusco, oem forester, etc.) cooler are a little redundant and not as effective?

Meaning... aren't all cars with a radiator effectively like a giant "water-to-oil" cooler already? ...especially since all the coolant passes inside the head and block already and is already cooling the same thing - the oil and the block. Wouldn't re-routing the lines be effectively almost the exact same thing as just leaving it bone stock with no water-to-oil cooler? Idk...just the way I see it, Lol. Anyone else think this too, or am I the only one? I can't really see this(a water-to-oil cooler) being much different than stock or being much different without one.

Just sounds a bit gimmicky to me. And, if you think a forester having a similar water-to-oil cooler as oem means it's not a gimmick; then why didn't they put it on all subaru models? Maybe subaru saw that it didn't really work, so they didn't put it on their other models.

subaru actually have used a variation of the forester cooler (no cup because bottom mount, and a couple versions of fitting orientation) on all the turbo models iirc.

Granted historically the unit has been more referred to as an "oil warmer" over on places like nasioc the results shown in various posts here on this platform do show that it at least has some positive effect with regard to regulation, temperature drop time, and warmup time.

Wether these methods are as effective as an air to oil cooer is not up for debate, they aren't, in terms of pure oil cooling the air-oil coolers are superior. But cooling isnt the sole factor to be considered. For many especially those in colder climates oemish water-oil offers other aspects that are very appealing (winter advantages, less risk of leak, etc).

[CSG Mike]

There are pros and cons to both, but for the average person, oil-air will be superior.

We DO have a lot of oil-water experience (S2ks come with one from the factory and we use a rather large unit when we boost), and are nice when you have packaging constraints due to limited space, but if you have the space, always use an oil-air cooler.

[glamcem]

theoretically, water to oil coolers combined with a bigger radiator will help reducing the oil temps ..at least, this is the case with many cars that come with water to oil coolers from factory, you basically upgrade radiator not because your OEM radiator isn't sufficient to keep the coolant temps lows and steady but because it will help alleviate high oil temps...many Vette and Miata owners don't even bother changing the OEM oil cooler they simply upgrade their radiator and it does automatically..

We logged with my friend's Z06 before and after the bigger radiator (similar ambient temps).. and after adding a bigger radiator oil temps dropped to ~230 F from ~260F..

[Deep Six]

I realize there have been some issues with delivery, but my car has a Robi-Cooler and there are zero issues with oil or coolant temps getiing too hot in any condition. My only concern is that oil temps actually run 170's in the Florida winter which may be no issue at all.

[smbstyle]

At Sebring in the summer last year, oil temps hit 300*, and this past winter oil was consistently in the high 270*s.

To be quite honest, I have been against an air/liquid oil cooler for a while as I've seen plenty of cars catch fire due to an oil line leaking on track, and have done UOA's after each oil change, which includes several track days on each fill, and even when oil temps hit 300*, the UOA results were great. Even water temps were normal (~206-212*) while oil temps were sky high. Not only that, but from the race team engineers I have talked to, I have been told that high oil temps (270-300*) is more of a power issue than an engine reliability issue, due to the way engines, and more importantly oils, are made today. You also have more failure points in the oiling system and changing in oil pressures to deal with. That is one of the reason's why I like the idea of a liquid/liquid setup using the OEM Forester setup or Cusco kit, as I would much rather have a coolant line leak or fail than an oil line. However, for track use, I just don't think either of those are enough in severe climates like track events in the summer down south or out west.

With that said, I have been chasing lap times, and it is annoying how much power I will lose with high oil temps - a seriously noticeable power loss. I think you will gain more power on a track-use car by running an oil cooler vs. bolt ons like full exhaust and tune, and despite all of the negatives, I'm about ready to bite the bullet and go with an air/liquid cooler like the Jackson Racing or Perrin kit.

[ayau]

Originally Posted by smbstyle

At Sebring in the summer last year, oil temps hit 300*, and this past winter oil was consistently in the high 270*s.

To be quite honest, I have been against an air/liquid oil cooler for a while as I've seen plenty of cars catch fire due to an oil line leaking on track, and have done UOA's after each oil change, which includes several track days on each fill, and even when oil temps hit 300*, the UOA results were great. Even water temps were normal (~206-212*) while oil temps were sky high. Not only that, but from the race team engineers I have talked to, I have been told that high oil temps (270-300*) is more of a power issue than an engine reliability issue, due to the way engines, and more importantly oils, are made today. You also have more failure points in the oiling system and changing in oil pressures to deal with. That is one of the reason's why I like the idea of a liquid/liquid setup using the OEM Forester setup or Cusco kit, as I would much rather have a coolant line leak or fail than an oil line. However, for track use, I just don't think either of those are enough in severe climates like track events in the summer down south or out west.

With that said, I have been chasing lap times, and it is annoying how much power I will lose with high oil temps - a seriously noticeable power loss. I think you will gain more power on a track-use car by running an oil cooler vs. bolt ons like full exhaust and tune, and despite all of the negatives, I'm about ready to bite the bullet and go with an air/liquid cooler like the Jackson Racing or Perrin kit.

If only there was an easy way to import the BRZ RA edition oil cooler. OEM quality and fitment.

[Dezoris]

Originally Posted by AZP Installs

Sounds like a bad T-stat possibly?

-Mike Paisan

Not likely it would either never get hot or overheat right away. It does neither of those things.