Hydra Performance

Sergeant
Free Vendor
Jan 31, 2017
251
Gents,
All the latest >500PS M-cars use a water/air intercooler, with only a ~30mm thick heat exchanger blocking the radiator. It is also interesting to note that the B58-engined cars now come with a water/freon AC condenser to further maximize airspeed into the radiator core, this is very easily integrated into the low-temperature cooling circuit if you're already running a W2A core. I will be studying this carefully and will be posting more about it in my build thread shortly...
 
  • Informative
Reactions: JBacon335

Bnks334

Sergeant
Dec 1, 2016
269
New York
Gents,
All the latest >500PS M-cars use a water/air intercooler, with only a ~30mm thick heat exchanger blocking the radiator. It is also interesting to note that the B58-engined cars now come with a water/freon AC condenser to further maximize airspeed into the radiator core, this is very easily integrated into the low-temperature cooling circuit if you're already running a W2A core. I will be studying this carefully and will be posting more about it in my build thread shortly...
Might be worth reaching out to one of the teams running the B58 M240i in pirelli world challenge to see what they say in regard to cooling.
 

MDORPHN

Corporal
Jan 28, 2018
114
OK, some findings following three terrific days on track at VIR. As I posted earlier, I was seeing my IATs rise 75-80 degrees over ambient during 20-25 minute track sessions with my very large stepped intercooler due to heat soak. With the way smaller (and less costly), non-stepped 7" VRSF HD intercooler, the delta over ambient was 60-63 degrees -- a significant improvement.

Additionally, my coolant temps dropped 5-10 degrees (generally staying between 196 - 205 F), presumably because my CSF radiator got greater airflow.

Neil
 
  • 2Like
Reactions: Jeffman and RSL

Asbjorn

Sergeant
Mar 10, 2018
284
Europe, based in China
OK, some findings following three terrific days on track at VIR. As I posted earlier, I was seeing my IATs rise 75-80 degrees over ambient during 20-25 minute track sessions with my very large stepped intercooler due to heat soak. With the way smaller (and less costly), non-stepped 7" VRSF HD intercooler, the delta over ambient was 60-63 degrees -- a significant improvement.

Additionally, my coolant temps dropped 5-10 degrees (generally staying between 196 - 205 F), presumably because my CSF radiator got greater airflow.

Neil
This is hard to believe, and conflicts with my data. I know the 7 HD version is better than the nonHD but still... Also I did not see any significant improvement in coolant temps when moving from 7.5 to 7. If this is really happening, it might be because there is more room in front of the FMIC on a Z4.

Was the air density and temperature the same during these two tests? If the ambient temperature + humidity was lower your coolant radiator becomes more efficient, and your turbos spool slower, making the job easier for the FMIC. Also you need to take into account your driving (WOT%/power vs average speed). I typically note down both the weather app temp (temp at 2m) and the temp indicated in cluster on track (temp above the track surface), because a 100F day with no wind and clear skies will be a different cooling challenge compared to a cloudy 100F day with strong winds.
 

MDORPHN

Corporal
Jan 28, 2018
114
This intercooler is on my single turbo 1M -- not a Z4 -- and the ambient ranged from 48 degrees F to 74 degrees F. The IAT delta was the same regardless of ambient temp.

EDIT: Ambient range at VIR was 63 -77. Sorry!

Neil
 
Last edited:

Asbjorn

Sergeant
Mar 10, 2018
284
Europe, based in China
This intercooler is on my single turbo 1M -- not a Z4 -- and the ambient ranged from 48 degrees F to 74 degrees F. The IAT delta was the same regardless of ambient temp.

Neil
Please post your ambient temps and conditions (preferably a log that also shows driving) for each data point (7.5 vs 7). Especially coolant peaks are impossible to compare if we don't know if they happened in 74F or 48F. That's a huge difference in ambient conditions according to my experience.
 

MDORPHN

Corporal
Jan 28, 2018
114
Please post your ambient temps and conditions (preferably a log that also shows driving) for each data point (7.5 vs 7). Especially coolant peaks are impossible to compare if we don't know if they happened in 74F or 48F. That's a huge difference in ambient conditions according to my experience.
See edit to my earlier post. The 48 degree weather was 3 weeks earlier at Summit Point. Following is info from the three days I just spent at VIR.

Session 1: Ambient 63 - Peak IAT 125 (+62) Coolant 205
Session 2: Ambient 68 - Peak IAT 127 (+62) Coolant 209
Session 3: Ambient 70 - Peak IAT 135 (+65) Coolant 206
Session 4: Ambient 74 - Peak IAT 136 (+62) Coolant 201
Session 5: Ambient 76 - Peak IAT 136 (+60) Coolant 196
Session 6: Ambient 77 - Peak IAT 133 (+56) Coolant 198

Each session 20-25 minutes on VIR Full Course. Max 24 psi boost.

Neil
 
Last edited:

berns

Corporal
Jan 15, 2018
113
See edit to my earlier post. The 48 degree weather was 3 weeks earlier at Summit Point. Following is info from the three days I just spent at VIR.

Session 1: Ambient 63 - Peak IAT 125 (+62) Coolant 205
Session 2: Ambient 68 - Peak IAT 127 (+62) Coolant 209
Session 3: Ambient 70 - Peak IAT 135 (+65) Coolant 206
Session 4: Ambient 74 - Peak IAT 136 (+62) Coolant 201
Session 5: Ambient 76 - Peak IAT 136 (+60) Coolant 196
Session 6: Ambient 77 - Peak IAT 133 (+56) Coolant 198

Each session 20-25 minutes on VIR Full Course. Max 24 psi boost.

Neil
What fuel are you running? What coolant are you running? What oil? I think if we're going to start talking about all of this stuff, it'd be best to paint the full picture to notice possible successful methods. Any vids?
 

MDORPHN

Corporal
Jan 28, 2018
114
What fuel are you running? What coolant are you running? What oil? I think if we're going to start talking about all of this stuff, it'd be best to paint the full picture to notice possible successful methods. Any vids?
93 octane. Distilled water with MoCool. Motul 300V 5W30.

Neil
 

berns

Corporal
Jan 15, 2018
113
93 octane. Distilled water with MoCool. Motul 300V 5W30.

Neil
Thanks Neil.
I might make the switch to E85 blend this year if I can find a good way to transport the fuel to the track in the trunk. Running 91 isn't fun...
I too am removing my VRSF 7.5" Race core in favor of the new CSF intercooler. Also cut up my nice Seibon hood and added a single vent. Will try to work on ducting soon.

YCJri5nl.jpg


qUBSxr2l.jpg
 
  • Love
Reactions: [email protected]

Asbjorn

Sergeant
Mar 10, 2018
284
Europe, based in China
What fuel are you running? What coolant are you running? What oil? I think if we're going to start talking about all of this stuff, it'd be best to paint the full picture to notice possible successful methods. Any vids?
Coolant and oil type doesn't really matter if you ask me. I tried it all. Again the M4 is fine all stock. What we are clearly seeing here is inconsistent driving, which is understable at a common track day. There might be traffic, yellow flags, brake wear etc that plays into it. We need full logs to be sure. I will try to group the data anyway in a sec.
 

Asbjorn

Sergeant
Mar 10, 2018
284
Europe, based in China
Below is how I would compare the results. I do not see that swapping from 7.5 to 7 HD made any significant improvements on the 1M. What I do see though, is that the nonHD 7 is a signicant inferior FMIC compared to both the HD version of the 7.5 and 7. It is also striking how much better @MDORPHN 's car is performing in terms of coolant peaks. China is probably more humid (less dense air), but still...

Anyway, I have taken the liberty to group the data into easy and hard modes depending on an evaluation of track and driving style on mine and MDORPHN's behalf. This is because, imho, a car that only peaks at 196 coolant in 76 ambient cannot have been pushed as hard as when it reached 209 in 68 ambient at the same track. This might have been reflected in lap times as well?

cooling.jpg


@MDORPHN
@berns

Let me know if any mistakes above
 
Last edited:

MDORPHN

Corporal
Jan 28, 2018
114
Asbjorn -

I suspect my single turbo (GTX3576r) heats things up a lot less than your twins.

FWIW, I also have Swaintech White Lighning on my downpipes and manifold and a vented hood. I was also running with my MHD tune set to its coolant track mode.

Neil
 

Asbjorn

Sergeant
Mar 10, 2018
284
Europe, based in China
Asbjorn -

I suspect my single turbo (GTX3576r) heats things up a lot less than your twins.

FWIW, I also have Swaintech White Lighning on my downpipes and manifold and a vented hood. I was also running with my MHD tune set to its coolant track mode.

Neil
Yeah for iat it makes sense. But you mean the GTX is easier on the the coolant as well? Is that a fact I missed somehow? Maybe @[email protected] could comment?

Would be happy to learn something new here. I thought turbos were mainly oil cooled, and that the amount of oil that goes through a turbo, even at WOT, is rather insignificant...
 

[email protected]

Corporal
Platinum Vendor
Jun 4, 2018
136
Let me chime in here...

@Asbjorn... First, the previous intercooler on the 1M was not a VRSF 7.5. It was a custom intercooler made by a turbo shop. So you can remove that data point from your chart above to prevent confusion to other readers. Second, the E89s have a nautical mile of distance between the intercooler and the air inlet of the front bumper. The E82s do not. Extremely large intercoolers on E82s get airflow blocked by the front bumper/bumper support leading to heat soak of a large % of the heat exchanger when subjected to long term heat management such as track driving. You can get away with it street driving and on the drag strip because it is short term heat management. This is why track guys have to ignore magical dyno data with all this stuff.

As for single vs twin turbo heat... yes when comparing apples to apples it makes sense. But we aren't comparing apples to apples. You have to take into account boost levels and other things. The best way to definitively answer whats going on is to have a pre-intercooler analog sensor logging temps. Can't do that with MHD, has to be done with an analog input capable data logger. Until then it is speculation. In other words, whats the pre-intercooler air temp of twins at ~15 PSI vs a single at ~24 PSI? Don't know until you log it. As you said, Chris at Vargas would be a good person to chime in on this.

As for cooling, its been determined already that regardless of what mode (stock settings or MHD track mode) the DME is trying to target 194 during high throttle/power demand. So ambient 68F with coolant temp of 209F versus ambient 77F with coolant temp 198F is an indication of deviation of average throttle % between the two sessions. The best way to do the comparison and get the full picture would be to do a histogram of throttle % between the two sessions. Can do via excel with an exported MHD log or (sorry to beat a dead horse) one click of a button with a true racing data logger system.

The fact that the DME is trying to target 194F and the coolant temp reached 209F with ambient 68F indicates to me the cooling system is insufficient to meet the demands of track driving. Once ambient temps get into the high 80s with moderate to high humidity I will be curious to see what the coolant temps will be. We patiently wait.

Finally, the turbos do have coolant running through them, not just oil. The N54 is all integrated into one system therefore turbo heat adds to the overall heat of the cooling system. Someone correct me if i'm wrong but the S55 has two cooling systems, a mechanical pump for main engine cooling and a separate electric pump system for turbo cooling. This indicates to me that it is significant additional heat and BMW wanted to combat that. Again someone please correct me if I'm wrong, not familiar with the S55 motors in detail.
 
Last edited:

berns

Corporal
Jan 15, 2018
113
Let me chime in here...

@Asbjorn... First, the previous intercooler on the 1M was not a VRSF 7.5. It was a custom intercooler made by a turbo shop. So you can remove that data point from your chart above to prevent confusion to other readers. Second, the E89s have a nautical mile of distance between the intercooler and the air inlet of the front bumper. The E82s do not. Extremely large intercoolers on E82s get airflow blocked by the front bumper/bumper support leading to heat soak of a large % of the heat exchanger when subjected to long term heat management such as track driving. You can get away with it street driving and on the drag strip because it is short term heat management. This is why track guys have to ignore magical dyno data with all this stuff.

As for single vs twin turbo heat... yes when comparing apples to apples it makes sense. But we aren't comparing apples to apples. You have to take into account boost levels and other things. The best way to definitively answer whats going on is to have a pre-intercooler analog sensor logging temps. Can't do that with MHD, has to be done with an analog input capable data logger. Until then it is speculation. In other words, whats the pre-intercooler air temp of twins at ~15 PSI vs a single at ~24 PSI? Don't know until you log it. As you said, Chris at Vargas would be a good person to chime in on this.

As for cooling, its been determined already that regardless of what mode (stock settings or MHD track mode) the DME is trying to target 194 during high throttle/power demand. So ambient 68F with coolant temp of 209F versus ambient 77F with coolant temp 198F is an indication of deviation of average throttle % between the two sessions. The best way to do the comparison and get the full picture would be to do a histogram of throttle % between the two sessions. Can do via excel with an exported MHD log or (sorry to beat a dead horse) one click of a button with a true racing data logger system.

The fact that the DME is trying to target 194F and the coolant temp reached 209F with ambient 68F indicates to me the cooling system is insufficient to meet the demands of track driving. Once ambient temps get into the high 80s with moderate to high humidity I will be curious to see what the coolant temps will be. We patiently wait.

Finally, the turbos do have coolant running through them, not just oil. The N54 is all integrated into one system therefore turbo heat adds to the overall heat of the cooling system. Someone correct me if i'm wrong but the S55 has two cooling systems, a mechanical pump for main engine cooling and a separate electric pump system for turbo cooling. This indicates to me that it is significant additional heat and BMW wanted to combat that. Again someone please correct me if I'm wrong, not familiar with the S55 motors in detail.
Here are some logs at Buttonwillow Raceway. Typical warm days with insane temps.
91 Octane, Red Line 10w40, OEM coolant with water wetter (I know... Will change to distilled water once the body work is done)
Stock turbos, stock location silicone inlets, VRSF Race FMIC, CSF Radiator, custom twin Setrab oil cooler with no thermostat.

 

Asbjorn

Sergeant
Mar 10, 2018
284
Europe, based in China
Here are some logs at Buttonwillow Raceway. Typical warm days with insane temps.
91 Octane, Red Line 10w40, OEM coolant with water wetter (I know... Will change to distilled water once the body work is done)
Stock turbos, stock location silicone inlets, VRSF Race FMIC, CSF Radiator, custom twin Setrab oil cooler with no thermostat.

I've added this data above, assuming 100F ambient. Thanks for the data point.
As stated earlier do not expect any improvements by swapping to distilled water. I already tried that, and certainly cant recommend it.
 

Bnks334

Sergeant
Dec 1, 2016
269
New York
You absolutely cannot compare data from two different tracks.

I have never ever had a cooling issue at lime rock even in 9xf heat; however, at Pocono my car was seeing 28xf oil and 230f coolant and 170f iats. Completely different tracks and topping out 5th gear on the longest straight in NA really adds to the heat.

Distilled water absolutely will improve cooling. It's a proven fact lol. I can see a notable difference between water and a 50/50 mix. Will it translate out to 50f cooler? no. Will PEAK coolant temps change? probably not. What will change is how quickly the heat exchange occurs. straight water without a doubt transfers heat better than glycol. This assumes your radiator isn't blocked and can adequately exchange the heat back out to the air.
 
Last edited:
Top