N54 Cooling - Temp Control Logic and what are your temps during extended track use?

[scrllock]

Haha, no, though I've been fighting leaks for months, just recently replaced my rad with an oem one and trying not to second-guess it too much.
The concern is over-cooling, particularly since I drive the car at subzero temps on the highway. Lots of reviews of the csf unit with thermostat warnings, no heat, etc. Unclear to me if that's specific to the AT version however, or if any of the coolant logic discussed here could be used to negate this.
And yes, it works similarly, there's a "heater core" that transfers heat between the oem trans cooler and the radiator. The trans cooler kits I've seen plug it off and run independently, but I would probably try to have it in sequence with a t-stat to accommodate winter here.

 

[Asbjorn]

Haha, no, though I've been fighting leaks for months, just recently replaced my rad with an oem one and trying not to second-guess it too much.
The concern is over-cooling, particularly since I drive the car at subzero temps on the highway. Lots of reviews of the csf unit with thermostat warnings, no heat, etc. Unclear to me if that's specific to the AT version however, or if any of the coolant logic discussed here could be used to negate this.
And yes, it works similarly, there's a "heater core" that transfers heat between the oem trans cooler and the radiator. The trans cooler kits I've seen plug it off and run independently, but I would probably try to have it in sequence with a t-stat to accommodate winter here.

Please show/link to an example/log of a CSF equipped N54 that can't get up to temp in freezing ambient temps. Personally I have had no such problem, and since we have an electric water pump that can turn off or slow down to heat the engine, as well as a thermostat that can close the main radiator, I am not sure it is possible (even if the csf radiator was an actual significant upgrade, which is really isn't)?

Sounds more like examples of the thermostat failing?

 

[scrllock]

BMW 3-Series (E90 E92) Forum - View Single Post - CSF Upgraded Radiator for AT cars?

Forum for BMW 1-Series 3-Series 5-Series 7-Series M3 M5 M6 Z4 X1 X3 X5 X6 Z2 Z4 325i 330i 335i 535i 550i 755i BMW Forums

www.e90post.com

I think I over-cooled my car...no heat with custom oil cooler + aluminum radiator - JB4tech.com - International Turbo Tuning Discussion

I think I over-cooled my car...no heat with custom oil cooler + aluminum radiator N55

www.n54tech.com

Mishimoto radiator?

anyone running one of these? If so, did you see any benefit from making the switch? Had to drain the coolant to have my turbo shipped and inspected, so now is a good time to make the switch if it's worth the $620 shipped prices I've seen.

bmw.spoolstreet.com

Those are the ones I was able to quickly find that were firsthand accounts. I'm sure it's a little bit of exaggeration that's spread, but it gets down to -28C (if i'm converting properly) here sometimes, and a working heater is a must-have QoL item.

 

[Asbjorn]

BMW 3-Series (E90 E92) Forum - View Single Post - CSF Upgraded Radiator for AT cars?

Forum for BMW 1-Series 3-Series 5-Series 7-Series M3 M5 M6 Z4 X1 X3 X5 X6 Z2 Z4 325i 330i 335i 535i 550i 755i BMW Forums

www.e90post.com

I think I over-cooled my car...no heat with custom oil cooler + aluminum radiator - JB4tech.com - International Turbo Tuning Discussion

I think I over-cooled my car...no heat with custom oil cooler + aluminum radiator N55

www.n54tech.com

Mishimoto radiator?

anyone running one of these? If so, did you see any benefit from making the switch? Had to drain the coolant to have my turbo shipped and inspected, so now is a good time to make the switch if it's worth the $620 shipped prices I've seen.

bmw.spoolstreet.com

Those are the ones I was able to quickly find that were firsthand accounts. I'm sure it's a little bit of exaggeration that's spread, but it gets down to -28C (if i'm converting properly) here sometimes, and a working heater is a must-have QoL item.

Very interesting!!

Alot of examples here where coolant wont go above 140-160F, and cabin heater doesn't work. The thermostat should be shutting off the main radiator at those temps, and 140F is plenty hot for cabin heating. So what is going on?

Now because the cabin heater is on, the water pump is running at low speed and the thermostat is off, sending coolant to the engine, heater and transmission heat exchanger connected to the AT core. Now someone mentioned that there's no separation between the AT core and main radiator on the CSF.

Mishimoto radiator?

anyone running one of these? If so, did you see any benefit from making the switch? Had to drain the coolant to have my turbo shipped and inspected, so now is a good time to make the switch if it's worth the $620 shipped prices I've seen.

bmw.spoolstreet.com

This might explain everything. It means that coolant still flows through the entire radiator entering in two places and then exiting through the transmission heat exchanger, even though the thermostat is closed. So the flow that should have gone to the cabin heater, actually enters the radiator instead and exits though the transmission heater. And the entire radiator is active, although at reduced flow, even when the car is warming up, and the thermostat is closed. This also explains why pinching the return line from the transmission heater helps, as more coolant is directed through the cabin heater instead of the entire radiator.

I will try and check my oem radiator to see how it was originally supposed to flow.

 

[scrllock]

That sounds like a pretty reasonable explanation given what I've read and the solutions people have proposed (most just tape over the kidney grilles it seems). Unfortunately no one that's tried it seems to have logged trans temps. I think @Payam@BMS might have done some with their transmission cooler, but they separate it from the heat exchanger and I think they said they only tested down to near-freezing, not sub-zero. I know this is a little off-topic given track use, but I'd be eager to find a good year-round solution that can keep the heater core and trans fluid adequately warm.

 

[Asbjorn]

That sounds like a pretty reasonable explanation given what I've read and the solutions people have proposed (most just tape over the kidney grilles it seems). Unfortunately no one that's tried it seems to have logged trans temps. I think @Payam@BMS might have done some with their transmission cooler, but they separate it from the heat exchanger and I think they said they only tested down to near-freezing, not sub-zero. I know this is a little off-topic given track use, but I'd be eager to find a good year-round solution that can keep the heater core and trans fluid adequately warm.

I found my old oem radiator. The AT and main cores are indeed separate. Some 6 rows or 13-14% of the radiator is used for heating and stabilizing the DCT.

Now we just need to confirm if the rumour about the CSF AT not having separate cores is true.

 

[houtan]

I found my old oem radiator. The AT and main cores are indeed separate. Some 6 rows or 13-14% of the radiator is used for heating and stabilizing the DCT.

Now we just need to confirm if the rumour about the CSF AT not having separate cores is true.

Based on the response i received from csf a few years ago, 7046 has separate circuits as well. I had emailed them asking about plugging up the holes to the AT heat exchanger if I got rid of it one day. This was the response. Not sure if anything has changed since then.

 

[Asbjorn]

Finally got around to do a proper A-B test of the second aux radiator I installed behind the FMIC.

I have a ball valve on the hose going to it, making it easy to do back-to-back testing. Here's the results form the test, it seems to reduce peak coolant by 5F:

Weather at the time of logging:
Day, clear
26C / 79F indicated in cluster
25C / 77F indicated on weather app
36% rH humidity on weather app
1011mb pressure on weather app
almost no wind
not far from sea-level.

First test: All coolers on + WI:
Peak iat 111F 44C
Peak dct 217F 103C
Peak oil 262F 128C
Peak coolant 223F 106C

Second test: As test number 1, but with the 2nd aux radiator turned off:
Peak iat 111F 44C
Peak dct 210F 99C
Peak oil 262F 128C
Peak coolant 228F 109C

First test:

Hide legend Reset zoom

 

[Asbjorn]

Second test

Hide legend Reset zoom

 

[MDORPHN]

FWIW, shop is replacing the stock "auxilliary" coolant radiator on my 1M with a much larger Derale unit today. Together with the Wagner Evo 3 ic, lots of new heat shielding and additional venting, I'm expecting a much cooler car.

Neil

 

[gmx]

119C peak oil temp after 3 consecutive laps on this circuit. Same config, same oil. Coolant was at 89C down the straight. Ambient temp around 22-27C peak. Track temp would've been pretty high as it clear with the sun blazing and the tyres didn't like it and the lap times showed. My fastest, relatively mistake free runs were the morning and very last session on my last lap in the afternoon. Humidity was 71% in the morning and 53% by the last session.

Not my best lap but only recorded session. No logs since I lent my cable to another N54'r chasing power reduction issues throughout the day.

Next year/season is R comp time, avg RPM should be higher. Let's see the data then.

 

[Asbjorn]

119C peak oil temp after 3 consecutive laps on this circuit. Same config, same oil. Coolant was at 89C down the straight. Ambient temp around 22-27C peak. Track temp would've been pretty high as it clear with the sun blazing and the tyres didn't like it and the lap times showed. My fastest, relatively mistake free runs were the morning and very last session on my last lap in the afternoon. Humidity was 71% in the morning and 53% by the last session.

Not my best lap but only recorded session. No logs since I lent my cable to another N54'r chasing power reduction issues throughout the day.

Next year/season is R comp time, avg RPM should be higher. Let's see the data then.

Amazing to see that although it got warmer, your coolant improved while oil got at tiny bit worse since last time. Maybe you were just pushing for longer? Oil takes some time to get up to temp while coolant stabilizes more quickly. Anyway, 90C coolant in combination with 120C oil is really a dream come true for any track driven N54s. Some logs and exact information about ambient conditions would be great next time as you said.

Also really impressed with your driving. What kind of power does your car produce? Since your engine temps are so awesome, in your case I would definitely be more concerned about oil pressure.

 

[gmx]

Yes oil pressure, and MSL's CNC'd billet housing thermostat for easier daily driving is next. I'm still thinking of a logging setup that would accomplish my needs. 0-5v oil pressure sensor, RaceChrono + 10hz ext GPS. Overlay with the MHD logs - somehow. I don't like the idea of overlaying things. Sounds inaccurate apart from video which is just for show imo. I also don't want to extend the budget and scope to vbox, aim, Motec etc.

The tune is custom around OEM turbos peaking at 16psi and taper to 13psi by 6000rpm and 12psi by 6500rpm.

 

[berns]

Full session at Buttonwillow in 80*F ambient. Probably about 7 sustained hotlaps with laptimes averaging about 1:55
Garrett GTX3076r with a 16.8psi peak and CES Motorsports kit
E40 fuel
Twin Setrab 19-row oil coolers with RedLine 5w40
CSF Intercooler
CSF Radiator with distilled water only

datazap.me | berno | ST E40 v3 - Full session at Buttonwillow

datazap.me

 

[Asbjorn]

Nice lap! It seems those 1-series really like to dance with all that torque and stiff suspension.

To me the log confirms that you are mostly radiator limited in terms of cooling. But it seems you could easily do twice the number of laps, ie half an hour, without ever overheating at that pace and power level.

Your oil and coolant temps were really low in pit lane, were you running MHD track cooling?

 

[MDORPHN]

Felt the need to vent a bit...

 

[I am Jacks N54]

Stumbled on this relevant cooling overview on another site: https://f87.bimmerpost.com/forums/showpost.php?p=23595167&postcount=223

Interesting how far they went to separate oil and water temps.

 

[Asbjorn]

Stumbled on this relevant cooling overview on another site: https://f87.bimmerpost.com/forums/showpost.php?p=23595167&postcount=223

Interesting how far they went to separate oil and water temps.

Lots of good info there.

He later added two M4 aux radiators and a booster pump to drive them afaik. However the latest track videos he posted still showed pretty high coolant temps on track. Not limp mode high, but still way higher than Barry set out to achieve in this thread.

I tried to contact him by mail back when I was adding an aux radiator booster pump myself, but never heard back.

 

[MDORPHN]

Did a little carving on the bumper cover to get more direct airflow to the intercooler. Inlets on either side are for brake cooling ducts.

 

[rac]

Anyone had experience with aftermarket electric water pumps (from other platforms perhaps)? I'm considering ditching the stock pump as they are getting pricey locally to me, and I've had issues with cracked housings etc. Meziere, Davies Craig and others appear to have options that might be more durable. Compact size with sufficient flow rate is probably the criteria given our tightly packed engine bays. Running syvecs, not worried about control. Some of them have their own control units in any case.