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

matreyia

Major
Apr 19, 2017
1,780
711
0
Ride
335i e93
Sorry to thread jack, but, how do the BRAUM fit you? height/weight? do your shoulders land at a good spot above the belt openings?

Braum seats are yet to be installed. But I do hear good things about them from e93 owners. One owner even said he would never go back to stock M3 seats again.
 

matreyia

Major
Apr 19, 2017
1,780
711
0
Ride
335i e93
Don’t forget lightweight wheels and tires!

Oh yea...I got those already. I got the 313 model 18" wheels at 21lbs. per front wheel. Previous I had the big ass 5 spoke that weighed 34lbs each... shit! I shed probably 40 lbs of wheel weight which is multiplied x10 as regular weight so basically, 400 lbs. off the car.

Seats will take another 90 lbs off.
 
  • Like
Reactions: Jeffman

Asbjorn

Lieutenant
Mar 10, 2018
854
602
0
European, based in China
Ride
Z4 N54 DCT
Following the initial conclusions presented in this thread, I decided to jump ahead and add an extra coolant radiator. See detailed post in my build thread here. I should be able to do some logging during January, although not at +100F amb temps unfortunately :D

When ordering the radiator, I had to decide whether I wanted to leave enough space for my 7.5 HD race FMIC to be re-installed in the future. My calculations showed that in order to exceed the cooler area x depth of the S54, I would have to use all the space available above my current 7in FMIC. This means, if I keep the radiator in this position, I won't be able to fit a 7.5 FMIC. As I am only running 18-20psi, this should be fine, but others may want to consider placement elsewhere.

1665060716.jpg
 
Last edited:
  • Like
Reactions: Jeffman

barry@3DM

Corporal
Jun 4, 2018
155
264
0
@Asbjorn... nice! Can't wait to see the results!

I'm trying to wrap up some suspension items then i'll be going back to attacking the cooling stuff as well. Unfortunately minimal track days in the Mid Atalantic and certainly not hot these days for any good testing.
 

yuli8466

Specialist
Sep 6, 2018
99
23
0
Hi there, I track my 1M. I haven’t done anything to my cooling system yet and I’m also very concerned and let down by the oil temp. My car is stock turbo with JB4 running ~17psi peak, WT EVO III large inter-cooler, stock cooling system and cowl piece removed for theoretically better air flow out of the engine bay. Here in Guangdong, I have done ZIC and GIC in 80F+ days. For my last track day at GIC on 11.10, the ambient temp was ~80F. I was testing other things so I data-logged my pulls down the front and/or back straights. Here is the data for temps at the end of the straights:

Lap # - Oil Temp - Water Temp
==== 1 warm-up lap ====
Lap 1 - 219F - 196F
Lap 2 - 249F - 214F
Lap 3 - 258F - 214F
Lap 4 - 262F - 218F
==== 1 cool-down lap and ~3 mins in the pit with fan on 100% ====
Lap 5 - 233F - 199F
Lap 6 - 260F - 220F
Lap 7 - 271F - 221F
Lap 8 - 282F - 225F

It appears that if the oil temp can be kept below 260F, water temp should be under 220F.

As a protection, JB4 goes into safe mode when oil temp goes above ~285F. Therefore, I never reached 230F water temp since oil temp goes above 280F long before that. Ideally, I would love to keep my oil temps much lower, say ~240F.

I am now tempted to put in place a second oil cooler. However, I haven't decided where I want to place it. Currently, there are two possible locations:
  1. Remove the stock aux radiator on the driver side and replace with an oil cooler.
    • Pros:
      • easy fitment, easy bracket, no cutting, not interfering with anything else
      • able to vent hot air after cooler away from the engine bay and into wheel well
    • Cons:
      • space is limited so the size of the cooler cannot be too large
      • aux radiator deleted
  2. Behind front grille, in front of the radiator and above the intercooler.
    • Pros:
      • able to fit a large cooler
      • likely more air flow than the other location
    • Cons:
      • main radiator is blocked
      • hot air vented into engine bay
What do you guys think? Which is the better location for a second oil cooler? Also, given a second oil cooler, is upgrading the one in stock location still necessary?



Lap 1
View attachment 18172
Lap 2
View attachment 18173
Lap 3
View attachment 18174
Lap 4
View attachment 18175
Lap 5
View attachment 18176
Lap 6
View attachment 18177
Lap 7
View attachment 18178
Lap 8
View attachment 18179


我觉得你读书的时候,学习一定很好,论坛发帖,排版整齐,逻辑严谨,证据充分,英语地道。。。能把这种精神应用到玩车,厉害,真心佩服。
 

Asbjorn

Lieutenant
Mar 10, 2018
854
602
0
European, based in China
Ride
Z4 N54 DCT
@Asbjorn... nice! Can't wait to see the results!

I'm trying to wrap up some suspension items then i'll be going back to attacking the cooling stuff as well. Unfortunately minimal track days in the Mid Atalantic and certainly not hot these days for any good testing.

Just a quick heads up. I won't be able to test the new coolers this month due to dealing with other issues (boost and oil leaks). So I won't be able to present track log results until end of February unfortunately.
 

Asbjorn

Lieutenant
Mar 10, 2018
854
602
0
European, based in China
Ride
Z4 N54 DCT
Just a quick heads up. I won't be able to test the new coolers this month due to dealing with other issues (boost and oil leaks). So I won't be able to present track log results until end of February unfortunately.

I finally went to the track today to test the new coolers. It was 19C indicated outside, so not exactly hot. Unfortunately the session ended after only 6 minutes / 3 laps, due to a huge accident on track. A VW golf behind me ran out of braking, saw air time and ended up-side down. Fortunately the driver was alright.

I edited the csv file to include both C and F temps and uploaded to datazap:

https://datazap.me/u/asbjoern/gic-temperature-logging?log=1&data=5-14-22

Looking forward to get a full session 20min log next time
 

Asbjorn

Lieutenant
Mar 10, 2018
854
602
0
European, based in China
Ride
Z4 N54 DCT
Grrr... drove to Guangdong International Circuit with the purpose of finally logging a full session with the new coolers. Weather was dry, 75F... forecast said overcast, and there was no rain nearby according to the weather radar.

I set out. 2 hours later, very close to the track... drip drip drip... whooossh

I will stay here for the night and see if it gets better tomorrow, but chances are very slim.

24299



24300
 

barry@3DM

Corporal
Jun 4, 2018
155
264
0
Hate it when that happens. Driving in the rain is fun but when you have testing to do it sure does mess things up.
 

Asbjorn

Lieutenant
Mar 10, 2018
854
602
0
European, based in China
Ride
Z4 N54 DCT
So after a whole evening and night of rain, I woke up to sunshine today. I went to the track around noon, and was the first person to enter the track. There was still a bit of standing water on a few curbs bu otherwise a great day to test.

24370


Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.

Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;

Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.


Results

First I did 8mins of warm up, going faster and faster.


Then I did one cool down lap (not logged)

Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:


The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.


Conclusions

Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:


It is clear that:
  • The iat is more or less just following the ambient temp. This makes sense, because it is operating close to ambient temp, and I didn't change power or FMIC. With the 7.5 race FMIC, I think I had 10C lower peak iat, so nothing major.
  • It is also clear that peak coolant is lower (107C after many laps vs 118C before after one lap), but it is unknown how much is due to ambient temp and how much is due to the additional radiator. The decrease is somewhat similar to the decrease in ambient temp.
  • Transmission temp is a bit lower than coolant, and was also lowered by the same amount as ambient, and I didn't change anything there.
  • Engine oil temp is also doing better, but again similar to the decrease in ambient, although the factory location cooler was doubled in size since the 100F log.
So while I am happy I wasn't able to push any temperatures even close to power reduction today, I am still concerned what will happen in 100F weather. I had really hoped coolant would stay below 100C / 210F as demanded by the DME with the additional radiator, but it does sit in front of the other. I am not sure if I should be concerned with 106C / 223F peak coolant on track but let me know your thoughts.
 

barry@3DM

Corporal
Jun 4, 2018
155
264
0
So after a whole evening and night of rain, I woke up to sunshine today. I went to the track around noon, and was the first person to enter the track. There was still a bit of standing water on a few curbs bu otherwise a great day to test.

View attachment 24370

Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.

Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;

Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.


Results

First I did 8mins of warm up, going faster and faster.


Then I did one cool down lap (not logged)

Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:


The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.


Conclusions

Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:


It is clear that:
  • The iat is more or less just following the ambient temp. This makes sense, because it is operating close to ambient temp, and I didn't change power or FMIC. With the 7.5 race FMIC, I think I had 10C lower peak iat, so nothing major.
  • It is also clear that peak coolant is lower (107C after many laps vs 118C before after one lap), but it is unknown how much is due to ambient temp and how much is due to the additional radiator. The decrease is somewhat similar to the decrease in ambient temp.
  • Transmission temp is a bit lower than coolant, and was also lowered by the same amount as ambient, and I didn't change anything there.
  • Engine oil temp is also doing better, but again similar to the decrease in ambient, although the factory location cooler was doubled in size since the 100F log.
So while I am happy I wasn't able to push any temperatures even close to power reduction today, I am still concerned what will happen in 100F weather. I had really hoped coolant would stay below 100C / 210F as demanded by the DME with the additional radiator, but it does sit in front of the other. I am not sure if I should be concerned with 106C / 223F peak coolant on track but let me know your thoughts.


The extreme short is...

Historically, the coolant target for a BMW engine is no more that 200F for track use (M20, S14, M50, S50, M54, S54, list goes on). Above that they won't last very long. The long 6 cylinder heads (with the exception of the s14) like to warp and blow head gaskets at those temps on the track.

BMW says N54 Volumetric efficiency is 194F. My goal is no more than 200F.
 
  • Informative
  • Like
Reactions: Asbjorn and Torgus

RSL

Lieutenant
Aug 11, 2017
937
501
0
So after a whole evening and night of rain, I woke up to sunshine today. I went to the track around noon, and was the first person to enter the track. There was still a bit of standing water on a few curbs bu otherwise a great day to test.

View attachment 24370

Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.

Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;

Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.


Results

First I did 8mins of warm up, going faster and faster.


Then I did one cool down lap (not logged)

Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:


The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.


Conclusions

Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:


It is clear that:
  • The iat is more or less just following the ambient temp. This makes sense, because it is operating close to ambient temp, and I didn't change power or FMIC. With the 7.5 race FMIC, I think I had 10C lower peak iat, so nothing major.
  • It is also clear that peak coolant is lower (107C after many laps vs 118C before after one lap), but it is unknown how much is due to ambient temp and how much is due to the additional radiator. The decrease is somewhat similar to the decrease in ambient temp.
  • Transmission temp is a bit lower than coolant, and was also lowered by the same amount as ambient, and I didn't change anything there.
  • Engine oil temp is also doing better, but again similar to the decrease in ambient, although the factory location cooler was doubled in size since the 100F log.
So while I am happy I wasn't able to push any temperatures even close to power reduction today, I am still concerned what will happen in 100F weather. I had really hoped coolant would stay below 100C / 210F as demanded by the DME with the additional radiator, but it does sit in front of the other. I am not sure if I should be concerned with 106C / 223F peak coolant on track but let me know your thoughts.
It more likely was managed to target and was able to maintain it. The DME will control temps to 108C (ECO) and 104C (normal) unless changed. You won't get high or high+KFT modes/targets until ambient is 90 or 100F respectively (stock), so your sessions would have been targeted to 104-108C and they are right on that.

You should try reflashing your tune at least with MHD race cooling option selected before running next time. It will move all mode targets to 80-85C, except ECO. That will be a 20-28C target drop for the most part and then see how much lower actuals go when actively managed to cooler head temps. Ideally, ECO would be set to 80-85C as well, which is easy enough to do, but is not part of the MHD cooling pre-defined options.

You're not going to get a lot lower temps on stock cooling logics unless it's 100F outside. This is just driving around, but struggled to get oil to 180F on almost 80F day. Stock 335is hardware, no A/C (fan). FYI, fan shows ~7% when it's off, conversion factor is off. Temps are in C:
https://datazap.me/u/rsl/cooling-test-70c-target?log=0&data=3-4-5-7-8-9-11

Either way, MHD cooling is easy to add (select option and reflash current map with it) and would be noticeably better than stock if your coolers can keep up. My car has roughly 2:1 ratio on ECT drop to oil temp drop. Reduce max ECT 30-40F from stock targets, oil max temp drops about 15-20F. If it's cooler out, the ratio is less and max oil temp drops more per ECT. Not sure how it would be on track or with your rads, but just a ballpark on what to expect from oil by dropping ECT.
 
  • Like
Reactions: barry@3DM

Asbjorn

Lieutenant
Mar 10, 2018
854
602
0
European, based in China
Ride
Z4 N54 DCT
It more likely was managed to target and was able to maintain it. The DME will control temps to 108C (ECO) and 104C (normal) unless changed. You won't get high or high+KFT modes/targets until ambient is 90 or 100F respectively (stock), so your sessions would have been targeted to 104-108C and they are right on that.

You should try reflashing your tune at least with MHD race cooling option selected before running next time. It will move all mode targets to 80-85C, except ECO. That will be a 20-28C target drop for the most part and then see how much lower actuals go when actively managed to cooler head temps. Ideally, ECO would be set to 80-85C as well, which is easy enough to do, but is not part of the MHD cooling pre-defined options.

You're not going to get a lot lower temps on stock cooling logics unless it's 100F outside. This is just driving around, but struggled to get oil to 180F on almost 80F day. Stock 335is hardware, no A/C (fan). FYI, fan shows ~7% when it's off, conversion factor is off. Temps are in C:
https://datazap.me/u/rsl/cooling-test-70c-target?log=0&data=3-4-5-7-8-9-11

Either way, MHD cooling is easy to add (select option and reflash current map with it) and would be noticeably better than stock if your coolers can keep up. My car has roughly 2:1 ratio on ECT drop to oil temp drop. Reduce max ECT 30-40F from stock targets, oil max temp drops about 15-20F. If it's cooler out, the ratio is less and max oil temp drops more per ECT. Not sure how it would be on track or with your rads, but just a ballpark on what to expect from oil by dropping ECT.

You can see in the second log that coolant is at 90C before and after the hot laps. This indicates that dme has entered sport mode, probably due to pushing it during warm up and during the hot lapping.

We are modifying the cooler setup this week and I will try and include testing with and without race mode activated next time. May even turn the heater on lol.
 

Bnks334

Lieutenant
Dec 1, 2016
524
340
0
New York
Damn I guess this is one reason to avoid twin turbo setups. The GC lites have coolant flowing through them, right?
 

Bnks334

Lieutenant
Dec 1, 2016
524
340
0
New York
This is a reason to fix the programming. @jyamona

Filippo

I think it has actually been confirmed that the water pump will indeed run at full tilt in ALL cooling modes. So no, the car should not see rising coolant temps of 220f+ if it's running in normal mode targeting 205f.

The big difference the MHD cooling changes make is that you can force the car to run in "High+KFT" mode at all times (by lowering the ambient thresholds) which means that it will drop the coolant temp more aggressively in areas of the race track where coolant temps can be kept low. This then gives you more "headroom" again before temps rise again in the faster parts of the track that require a lot of throttle. so instead of entering the straight away with 205f coolant and peaking 230f you might enter the straight away at 180f coolant and peak 210f.

It works a little bit, but cooling capacity is still exceeded and coolant temps still trend upwards after successive laps.
 
  • Like
Reactions: Jeffman

RSL

Lieutenant
Aug 11, 2017
937
501
0
You can see in the second log that coolant is at 90C before and after the hot laps. This indicates that dme has entered sport mode, probably due to pushing it during warm up and during the hot lapping.

We are modifying the cooler setup this week and I will try and include testing with and without race mode activated next time. May even turn the heater on lol.
I shouldn't look at stuff at 2am, I missed the ends. I don't think it can be high or high+KFT, but oil temps, tranny, etc. can request additional cooling and maybe its hitting another mode besides those. There are 10 including fill/bleed, warm up, component protection, emergency, etc. I'm not sure if the outside requests have their own add tables like the heat balance table, change actual target in the same mode or trigger another mode like protection/emergency (80C).

Oil drops at a much slower rate vs. ECT than mine on the road, but that's probably expected.
 

shushikiary

Sergeant
Jun 4, 2018
304
173
0
Ride
335xi
How did you get that second radiator to fit? From the description it sounds like its sitting above the FMIC, thus you didn't push the stock radiator back at all?