Oil Cooling - An In-Depth Look

[bluesubie]

Originally Posted by nikitopo

Another suggestion is to use 5W30 oil. Subaru Germany suggests this grade. I'm not sure if Toyota Germany uses a 0W20 oil.

Subaru Japan allows Euro 0W30 and 5W40 in the BRZ. I know the German Foresters allow thicker viscosity oils so I would expect that thicker oil is allowed in the BRZ as well.

When changing oil grade, I do believe that people tend to focus too much on the number on the bottle and should be focusing on HTHS. Thinner viscosity oils typically run cooler, but higher HTHS is what maintains oil pressure (less shearing) and protects your bearings.

[Ultramaroon]

Originally Posted by gtengr

any updates?

I'm not going to make May. Plumbing parts are trickling in. One of them is a unicorn; a 90-degree -12AN x -8BSPP adapter for the Mocal plate. Found that one through Grainger.

[Tor]

That looks extremly error prone. Just tape the cooler off in the winter.

[steve99]

+1 agree, looks nice but all those fittings and changeover valve all points of failure/leakage


Normal Thermostatic sandwich plate and then as @Tor says just blank off cooler in winter if needed with plastic plate or tape. Far less to go wrong.


Im lucky though it never get cold ;-)

[Tor]

This completely disables the cooler, no flow no cooling. Checked with ECU logs.

If less ghetto is desired, one could make a carbon plate that clips on somehow. The remaining open area is more than sufficient for the water cooler. That's checked with logs as well.

[Ultramaroon]

Show me a setup that can maintain below 95C in the harshest conditions and still warm up adequately for a daily driver.

I agree it looks fragile. This is just a first stab. It will either evolve or end up on a shelf.

[Calvin27]

Originally Posted by Ultramaroon

Show me a setup that can maintain below 95C in the harshest conditions and still warm up adequately for a daily driver.

I agree it looks fragile. This is just a first stab. It will either evolve or end up on a shelf.

Most thermostatic systems should do that. I didn't hit 200F on track day running 40 min continuously on a 36C day (185F thermostat w mishimoto 18 row). Warm up time is not really longer than having no cooler - the oil gets up to temp faster than the coolant.

I was a bit concerned about this pre-cooler. I think I acutally suggested the valve arrangement a whiel back.But all is good. the thermostat works. I would have liked a smaller 10 row cooler to give the radiator more space to breath but neither has been a problem so far.

[Ultramaroon]

Originally Posted by Calvin27

Most thermostatic systems should do that. I didn't hit 200F on track day running 40 min continuously on a 36C day (185F thermostat w mishimoto 18 row). Warm up time is not really longer than having no cooler - the oil gets up to temp faster than the coolant.

I was a bit concerned about this pre-cooler. I think I acutally suggested the valve arrangement a whiel back.But all is good. the thermostat works. I would have liked a smaller 10 row cooler to give the radiator more space to breath but neither has been a problem so far.

Be glad you got the 18-row. Your oil pressure would take a big hit with the 10-row.

[Tor]

Originally Posted by Ultramaroon

Show me a setup that can maintain below 95C in the harshest conditions and still warm up adequately for a daily driver.

I agree it looks fragile. This is just a first stab. It will either evolve or end up on a shelf.

This is a log with the cooler taped off at 7 C / 44 F ambient. There actually isn't a lot of difference with or without the tape, because specifically at warm up the thermostat works the best, since most oil will bypass the cooler anyway.



Rpm generally between 2500 bis 3000. Speed max 80 kph / 50 mph. Notice how the temperature rise plateaus everytime I come to a standstill and the engine is at idle (it needs moderate rpm to build heat).

Oil temp was (yellow line):
60 C / 140 F deg after 5 min 3 sec (Water 170)
70 / 158 after 6 min 42 sec (at the same time ECT hit 194)
80 / 176 after 10 min 3 sec
90 / 186 after approx 14 min

Note it's a 80 deg / 176 deg thermostat. Also, note that I could have sped up the warming by gradually increasing rpm.


The problem for me was actually keeping the temperature up. The cooler would cool too much at high speed and the thermostat either too slow to react, not reacting at all (residual heat as the sandwich plate is on top of the engine perhaps?) or the amount of oil not going through the bypass too little (i.e. too much flowing to the cooler with the bypass open).

Here with the cooler taped up and this time at -2 C / 28 F starting out driving up to 180 kph (110 mph):



Here you see oil keeping parallel with ECT at 90 C / 208 F. Once getting off the autobahn and standing in idle at a red light it drops to 89 / 192. Continue driving at lower revs it stays the same ballpark.

Here a log from yesterday with the tape removed:



This is 5 laps on a Formula One racetrack at 15 C/ 59 F ambient. Max oil temp 103 C / 217 F.

In the summer time on track I get up to 115 C / 239 F.

[200hp/tonne]

With all the complex plumbing systems being made for cold/warm options, has anyone investigated a Laminova or Fluidyne coolant to Oil heat exchanger solution?
Fluidyne part I am considering:
https://www.summitracing.com/parts/f...0500/overview/

With the huge flows this unit is capable of, I was thinking to put this heat exchanger in series with the heater core and normal sandwich plate for oil flow

[Ultramaroon]

Originally Posted by Tor

In the summer time on track I get up to 115 C / 239 F.

I am excited to share my results here regardless of outcome. Your experience illustrates the issues that I hope to address; overcooling on the highway while undercooling on the track.

Another part of my setup, which until now I haven't discussed, is the oil cooler itself and my choice of plumbing. It's a Setrab 72-row 1-series being fed by -12AN plumbing. Why so outrageously huge? Minimum pressure loss.

With thermostatic control and the ability to adjust cooler flow the results will be interesting.

Remember folks, it's an experiment.

[7 skulls]

Interesting thread. Since I have the Cusco oil/water cooler already installed on my car, I was going to mount a Setrab core in front of the radiator and plumb it ahead of the Cusco heat exchanger with an electronically controlled butterfly valve. I have the valve, hoses and adapters. Then I did some research and figured out why it wouldn't work. So, I bought an AVO Turboworld oil cooler instead.(still not installed).
Good luck with the experiment.

[Tor]

Originally Posted by Ultramaroon

I am excited to share my results here regardless of outcome. Your experience illustrates the issues that I hope to address; overcooling on the highway while undercooling on the track.

I got it that you want to experiment.

But I don't have under cooling on track. I specifically targeted 115 deg C peak. I think this is a sensible temperature where the oil won't degrade at an extreme accelerated rate.

The Toyota CS-V3 Cup racer comes with only a 6 row Setrab oil cooler, delivered like that from Toyota Racing GmbH. They drive those for 4 hours straight at the Nürburgring. Of course, they have other considerations and for sure change oil after each race. Also, they use 15W60 oil.

Oil temperature is a balance of a lot of things. For a pure racecar higher oil temperature is desirable because it means less friction. Which means more HP reaching the wheels. So in the above example, they don't cool the oil that much, hence need another viscosity and have to throw it away after each race.

Since I don't want to change oil every weekend and also want to drive the car on the road I have a 13-row cooler and run 0W20 as specified. Occasional 115 deg C won't break the oil down more than I can get away with changing it each 5-7000 km (3100-4300 miles).

Over cooling is only at sub 10 deg (50 F) ambient. That mean late fall/winter/early spring - where I don't track the car. Here the solution is easy: I just tape it off. If I was to go to an odd track day out of season I could just remove the tape and drive. Before going home I could tape it up again. Takes less than a minute.

[Cybmx]

I made this little plastic blocker, and it's secured by reusable zip-ties.