solutions for oil temp on track

[Z4m40i]

Engine Mods: BM3 stage 2 OTS w/ flex fuel, e50, AA downpipe, akrapovic exhaust, wagner intake manifold, liquimoly 5w30 special tec
ambient temperatures 80F and sunny, 20-30mph winds.

Last weekend I was at Las Vegas motorspeedway outside track. I shared my car with my brother for his first HPDE experience. There were 40 minute cool down periods between my group and his, and another 1.5 hours until I would start again. At this point in the data log, the car has had about 1.5hrs of track time. I was vigilant about taking cooldown laps and getting back onto the public road to get the car to cool down. The car was always reactive to cooling down fast. I have alarms set on my bm3 for oil (275F), coolant (230F) and trans (230F). I had the top down on my run and didn't even realize my temp alarms were going off during my run. I only noticed after checking the data logs. I'm a little surprised that the car doesn't give any errors with temps being so high.

I'm under the impression that the general conscious that auxiliary heat exchangers and radiator upgrades yield negligible changes. Obviously, these temps are unacceptable but is the only solution to just have longer cooldown periods? Oil is being sent out to blacklab for analysis.

https://www.bootmod3.net/log?id=661ac50b7347152440e4aa37

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[razorlab]

Too much boost on stock turbo with the OTS E50 mapping for track use. Heats everything up a ton.

looks like around 21 psi at 6500 rpm. Stock turbo is a hair dryer at that point.

Car is def pulling timing at 140f IAT

 

[i3igpete]

according to this post, the numbers you're seeing are not uncommon. that being said, 275 f oil temps are also ingrained in my brain as alarm bells, but I suppose that is ok on this platform.

https://www.supramkv.com/threads/race-tracking-your-supra-information-exchange.16389/post-345527

 

[Z4m40i]

Too much boost on stock turbo with the OTS E50 mapping for track use. Heats everything up a ton.

looks like around 21 psi at 6500 rpm. Stock turbo is a hair dryer at that point.

Car is def pulling timing at 140f IAT

I was thinking more ethanol, the cooler the combustion temps but I guess the stock turbo is just out of the efficiency range at this point. Even though IAT's are high, I am impressed how much the wagner is able to bring down the temps from the pre-throttle measurement.

As far as solutions go, it sounds like running less ethanol or a larger turbo seems to be the direction?

 

[i3igpete]

aside from hood vent, I'm thinking that going to a catless downpipe would reduce overall temps. since a catted downpipe is, by definition, performing a secondary exothermic reaction within a few inches of the engine block.

 

[Z4m40i]

according to this post, the numbers you're seeing are not uncommon. that being said, 275 f oil temps are also ingrained in my brain as alarm bells, but I suppose that is ok on this platform.

https://www.supramkv.com/threads/race-tracking-your-supra-information-exchange.16389/post-345527

I'm still trying to read all the info in that thread and I started at the beginning about a week ago lol. While I see these engines running hot but cooling down pretty fast, there have been mixed information about oil temp thresholds. Some have said synthetic oils begin sheering and breaking down at 270F, but others have said they're good for 300+F.

 

[i3igpete]

So, I probably know more about oils than I care to talk about, but it general, all oils are LESS sensitive to shear strain rate at high temperatures than low temperature. Consider figure 8, on a logarithmic Y-axis, the 323K drop is larger in magnitude than the 423K drop.

Beyond that, some synthetics are resistant to shear-thinning dependency (see fig 6, s0530-1) but this is not true of all synthetics. Note that this is dynamic shear, not the same as aging shear.

Taken from J.Sorab (1993). full text: https://www.sae.org/publications/technical-papers/content/932833/:

Some guidelines I wrote:

 

[Evolution]

I just wanted to say, I saw you out there at LVMS. Not many Z4s out there. What kind of times were you running?

 

[Z4m40i]

I just wanted to say, I saw you out there at LVMS. Not many Z4s out there. What kind of times were you running?

It was cool to see a lot of supras out. Usually I see one, maybe two, at willow springs and only one at laguna.

Did a 2:02:21. Had continental ECS02's on- they wore great but got greasy only after 2.5 laps. Not the best tire for that course.

 

[razorlab]

I was thinking more ethanol, the cooler the combustion temps but I guess the stock turbo is just out of the efficiency range at this point. Even though IAT's are high, I am impressed how much the wagner is able to bring down the temps from the pre-throttle measurement.

As far as solutions go, it sounds like running less ethanol or a larger turbo seems to be the direction?

Yes but ethanol can only do so much cooling. Yes, the wagner manifold works really well. Imagine what your IAT's would be without it!

I went larger turbo mainly for efficiency reasons. It creates way less heat than cranking the boost up on the oem turbo.

I created a virtue channel in my log viewer tool which shows how much heat my wagner manifold sheds from the intake charge. It's satisfying to see it sheds A LOT of heat from the intake charge. In some instances, it sheds more than 200F!

Here is an example of that. Also, this log is from a 15 lap session in around 83F ambient temps. You can see I have much less oil temps and actually all my temps aren't too crazy.

All coolers are OEM except for the Wagner intake manifold.

Start of session and then 15 laps in:

15 laps in:

 

[Z4m40i]

Yes but ethanol can only do so much cooling. Yes, the wagner manifold works really well. Imagine what your IAT's would be without it!

I went larger turbo mainly for efficiency reasons. It creates way less heat than cranking the boost up on the oem turbo.

I created a virtue channel in my log viewer tool which shows how much heat my wagner manifold sheds from the intake charge. It's satisfying to see it sheds A LOT of heat from the intake charge. In some instances, it sheds more than 200F!

Here is an example of that. Also, this log is from a 15 lap session in around 83F ambient temps. You can see I have much less oil temps and actually all my temps aren't too crazy.

All coolers are OEM except for the Wagner intake manifold.

Start of session and then 15 laps in:

15 laps in:

If only they made the pure700 still . I might have to go pure650 or daw hypercore then.

A couple of questions- do you think you hood vent is making a big difference for temps, or is that more for removing turbulent air in the engine bay? Also, did you notice a difference in trans temp running the M trans pan? I can't believe the temp deltas between our logs in similar ambient temps.

 

[razorlab]

If only they made the pure700 still . I might have to go pure650 or daw hypercore then.

A couple of questions- do you think you hood vent is making a big difference for temps, or is that more for removing turbulent air in the engine bay? Also, did you notice a difference in trans temp running the M trans pan? I can't believe the temp deltas between our logs in similar ambient temps.

I wouldn't say the vent made a big difference but it helps keep the overall gain of temps down.

Still running OEM pan. Plan on changing my trans fluid this month sometime.

 

[theQuaybee]

Hey there, welcome to the high-temp shitshow these cars are! I feel your pain and have been fighting this since I got the car. I've hit 300*F oil temps and power cut I think every track day, even in 70*F weather, literally until I put a big hood vent in this past week. My IATs would regularly get over 140 if it was higher than 85* out also.

I've sent oil to blackstone and changed every time and they've all come back just fine. Hell, the 2020 ZL1 1LE that I came from would be 275-290 every track day and that was with 20 coolers, hood vents, and huge front grill, all stock. Pretty fine these days with modern synthetic oil.

I am stock tune with CSF heat exchanger, aux rads, trans cooler, and an AMS intake mani. Whether the CSF stuff has helped, I honestly don't know.

Anyway, what I'm not ok with is timing pulls and power cuts when trying to enjoy a track day. A hood vent helped me greatly. I went with the 777 GT-4 style one, just got it on last week. Here's the difference the vent alone made for me:

Pre-vent log
Ambient temp: 72°F
Within 6 minutes (a few 1.8 mile laps):
Oil: 302°
Coolant: 237°
IAT: 138°
Obviously, power was cut, a lot, cooldown(s) required or exit session early

Post-vent log (last weekend)
Ambient temp: 80-82°F
Entire 20 minute session, 3.1 mile course, no traffic, full send
Oil: maxed at 293°, but would actually recover to 275° at times, which is a first
Coolant: maxed at 235°
IAT: maxed at 135°
No cool down laps, no power cuts

Still hotter than I'd like and I'm continuing to work on other options to try to help keep cool. But the vent alone made quite a big difference.

 

[Z4m40i]

I am stock tune with CSF heat exchanger, aux rads, trans cooler, and an AMS intake mani. Whether the CSF stuff has helped, I honestly don't know.

I appreciate you sharing your experiences- When I was running the stock intake manifold, I would have timing pulled about 6-7 minutes into my session. The Wagner manifold definitely allowed me to enjoy most of the sessions without timing being pulled. The log I posted was just the worst case scenario when there was only a ~30 min cooldown in between.

I've been looking into The BMS phenolic spacer to see if that helps. I did notice that my cruising IAT's run a few degrees hotter, but temps hardly budge even after a few pulls.

Are there any protections the car will use if the oil/trans/coolant temps are too hot? I experienced limp mode from IAT's when I blew one of the coolant lines leading to the manifold.

 

[theQuaybee]

Are there any protections the car will use if the oil/trans/coolant temps are too hot? I experienced limp mode from IAT's when I blew one of the coolant lines leading to the manifold.

I need to go check the same logs from the pre-vent data I posted up there, because my IATs were under 140F and I want to say I still got power cut. But again, need to go look. Here's the vid from that pre-vent data in case anyone's interested. Now that I'm looking back at it, it's worth noting that I had already done a few minutes of lapping before I got my data working. You can see my temps in the top right, but they don't come on until I reset my data around 12 minutes in.

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