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      06-14-2011, 12:16 PM   #397
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Quote:
Originally Posted by Chowbow View Post
I was under the impression that 117*C is the temp when the ECU puts the car into limp mode. Is that not correct? Or I'm at least sure that's pretty darn close. Do you guys know the exact temp?
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      06-14-2011, 12:38 PM   #398
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wonder if the DCI is playing a role. I switched back to the factory airbox. I wonder if the Mr. 5 Intake would solve your problems?
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      06-14-2011, 01:03 PM   #399
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I went through the issue in this thread a few years ago...

Logging the coolant temperature is great but it needs to be in format with other parameters over time so we have idea what truly is happening. Do not rely on the temperature gauge as the absolute temperature of the system because it is only reading at one specific location and there will be local boiling in other locations.

If chose to run 100% distilled water then you will reduce the boiling point by 7-8 degrees over 50/50 solution and not advisable without a wetting additive. The best comprise is running a solution mix 70/30 with a wetting additive. With this you get addition 6-15 C reduction (feedback from other a few years ago) in coolant temperature and possible more since the wetting agent is effective at reducing localized boiling areas which is a known problem in this engine. The flow rate of the coolant will increase due the decreased viscosity of the coolant as well. The wetting agent is effective with 30/70 but half of what you would see with 100 distilled water.

If you have tune (14-15 PSI max) then you need an upgraded IC and should consider oil cooler as well. Due to the massive increase in temperature pressure drop of the IC you are going to see power reduction before you hit any cooling threshold.

If you have auto transmission there are few tips you should consider. Run the transmission in manual mode. Turn traction control completely off. This is big issue with this transmission as intervention of the traction control system adds massive amount heat back into the transmission via clutch slippage which ends up back into the coolant system.

I stopped having any coolant issues (limp mode) once I turned off traction control. Changing the coolant to 30/70 mixture with a wetting additive goes a long way at reducing limp mode but it not enough if you are running with traction control on!
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      06-14-2011, 01:23 PM   #400
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/\ Thanks for the great post!
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      06-14-2011, 01:25 PM   #401
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Quote:
Originally Posted by Orb View Post
I went through the issue in this thread a few years ago...

Logging the coolant temperature is great but it needs to be in format with other parameters over time so we have idea what truly is happening. Do not rely on the temperature gauge as the absolute temperature of the system because it is only reading at one specific location and there will be local boiling in other locations.

If chose to run 100% distilled water then you will reduce the boiling point by 7-8 degrees over 50/50 solution and not advisable without a wetting additive. The best comprise is running a solution mix 70/30 with a wetting additive. With this you get addition 6-15 C reduction (feedback from other a few years ago) in coolant temperature and possible more since the wetting agent is effective at reducing localized boiling areas which is a known problem in this engine. The flow rate of the coolant will increase due the decreased viscosity of the coolant as well. The wetting agent is effective with 30/70 but half of what you would see with 100 distilled water.

If you have tune (14-15 PSI max) then you need an upgraded IC and should consider oil cooler as well. Due to the massive increase in temperature pressure drop of the IC you are going to see power reduction before you hit any cooling threshold.

If you have auto transmission there are few tips you should consider. Run the transmission in manual mode. Turn traction control completely off. This is big issue with this transmission as intervention of the traction control system adds massive amount heat back into the transmission via clutch slippage which ends up back into the coolant system.

I stopped having any coolant issues (limp mode) once I turned off traction control. Changing the coolant to 30/70 mixture with a wetting additive goes a long way at reducing limp mode but it not enough if you are running with traction control on!
100% distilled water with Mocool: Check
FMIC: Check
Oil Cooler: Check
Auto transmission in manual mode: Check (Would be crazy to attempt otherwise on the track)
traction control completely off: Check

All good points, at least in my case I'm already doing all of these.


Interesting comment about eliminating limp modes by turning off traction control, I didn't realize the effect on the transmission, I was under the impression that it kills rear pads only. Good info, thanks.
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      06-14-2011, 01:31 PM   #402
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Quote:
Originally Posted by UltraRacer13 View Post
wonder if the DCI is playing a role. I switched back to the factory airbox. I wonder if the Mr. 5 Intake would solve your problems?
It probably is. But wouldn't switching over to the stock airbox impede airflow for non-stock boost as well? Haven't looked at the Mr. 5 Intake yet.
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      06-14-2011, 02:12 PM   #403
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Quote:
Originally Posted by PeterM1 View Post
100% distilled water with Mocool: Check
FMIC: Check
Oil Cooler: Check
Auto transmission in manual mode: Check (Would be crazy to attempt otherwise on the track)
traction control completely off: Check

All good points, at least in my case I'm already doing all of these.


Interesting comment about eliminating limp modes by turning off traction control, I didn't realize the effect on the transmission, I was under the impression that it kills rear pads only. Good info, thanks.
Power reduction from the DME does not always happen so only braking only is implemented a lot of the time with traction control. The brakes are applied but the engine is still being driven so the slip points are the clutches. The parasitic load is dumped into the transmission oil then into radiator through the oil/water heat exchanger.

A lot of this is going come down to what tune you are running in the end.
You might want to upgrade the radiator next. Was going to try this but did not need it in the end. It has been around for 3 year and is it one other better one with a decent slat design.

http://www.pwrusainc.com/radiators.a...=All&id=7&sp=7
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      06-14-2011, 02:13 PM   #404
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Thanks for the chart Peter - good to know.

Quote:
Originally Posted by PeterM1 View Post
100% distilled water with Mocool: Check
FMIC: Check
Oil Cooler: Check
Auto transmission in manual mode: Check (Would be crazy to attempt otherwise on the track)
traction control completely off: Check

All good points, at least in my case I'm already doing all of these.


Interesting comment about eliminating limp modes by turning off traction control, I didn't realize the effect on the transmission, I was under the impression that it kills rear pads only. Good info, thanks.
I think what Orb means is that when the traction control comes on, the drivetrain slows down, but the RPMs are still up - which causes the difference to be absorbed by the slip in the torque converter, and that increases the temp of the trans fluid. Makes some sense actually as you look at the chart you posted. At a certain temp, the converter locks up so it cannot slip and the ECU is trying to minimize the heat generated from the transmission.
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      06-14-2011, 02:15 PM   #405
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Looks like he beat me to it while I was typing.
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      06-14-2011, 05:00 PM   #406
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When running a tune, I was going to say that a strong possibility would be traction induced limp modes. I saw in a follow-up post that you ran with it completely off, so it doesn't apply to you, but since nobody has mentioned this yet, I thought it was great to share and discuss.

Last year, I also triggered limp modes while running 10/10ths (DTC button pressed once), but no problems at 8/10ths. Oil temps were still normal.

After feeding this back to Shiv, he explained that it may be a traction induced limp mode, where the DTC logic was trying to dial boost back to 5psi, but the tune was still trying to hit 11-15psi (or whatever you have it set to).

He gave me a new set of PROcede maps/firmware to try w/ the early stages of his traction control feature, and my low oil temp limp modes went away next track day. I verified that the PROcede dialed boost back to what the ECU wants during traction controlled triggered events, but quickly builds back up to targeted levels once traction is regained, so the net effect is unoticeable (no feeling of being bogged down beyond what traction control was already doing).

Although this possibility doesn't apply to you, since you run w/ traction control OFF, I think it's valuable to share in this thread. We're doing a great job of identifying and discussing all the limp mode inducing causes on the track. I should draw up a fishbone diagram or something For those who don't know what it is, it's a common tool used in problem solving methodologies.

P.S. I bet you had no idea this thread would grow this big. But I guess unlike the other sub-forums on e90post, us track enthusiasts don't feel a need to start new threads for every point of discussion, lol. Otherwise, I may have done so, as this may be worth highlighting in a new thread since it's different from the typical oil and water induced limps we've been focusing on.

Quote:
Originally Posted by PeterM1 View Post
yep, that's why I mentioned that something else is going on, other than oil and water temps.

I was driving at 10/10s when I got the limp modes. Zero limp modes at 8/10s. Oil/water temps below thresholds at 10/10s.
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      06-14-2011, 05:25 PM   #407
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Quote:
Originally Posted by orionredwing View Post
When running a tune, I was going to say that a strong possibility would be traction induced limp modes. I saw in a follow-up post that you ran with it completely off, so it doesn't apply to you, but since nobody has mentioned this yet, I thought it was great to share and discuss.

Last year, I also triggered limp modes while running 10/10ths (DTC button pressed once), but no problems at 8/10ths. Oil temps were still normal.

After feeding this back to Shiv, he explained that it may be a traction induced limp mode, where the DTC logic was trying to dial boost back to 5psi, but the tune was still trying to hit 11-15psi (or whatever you have it set to).

He gave me a new set of PROcede maps/firmware to try w/ the early stages of his traction control feature, and my low oil temp limp modes went away next track day. I verified that the PROcede dialed boost back to what the ECU wants during traction controlled triggered events, but quickly builds back up to targeted levels once traction is regained, so the net effect is unoticeable (no feeling of being bogged down beyond what traction control was already doing).

Although this possibility doesn't apply to you, since you run w/ traction control OFF, I think it's valuable to share in this thread. We're doing a great job of identifying and discussing all the limp mode inducing causes on the track. I should draw up a fishbone diagram or something For those who don't know what it is, it's a common tool used in problem solving methodologies.

P.S. I bet you had no idea this thread would grow this big. But I guess unlike the other sub-forums on e90post, us track enthusiasts don't feel a need to start new threads for every point of discussion, lol. Otherwise, I may have done so, as this may be worth highlighting in a new thread since it's different from the typical oil and water induced limps we've been focusing on.
What code does this throw?

I threw a boost leak code on the track this weekend, but after an ECU reset via the Cobb AP it never came back.

The Cobb AP really is an amazing tool for logging. I bet with time they will add coolant temps to the logging parameters.
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      06-14-2011, 06:38 PM   #408
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Quote:
Originally Posted by orionredwing View Post
When running a tune, I was going to say that a strong possibility would be traction induced limp modes. I saw in a follow-up post that you ran with it completely off, so it doesn't apply to you, but since nobody has mentioned this yet, I thought it was great to share and discuss.

Last year, I also triggered limp modes while running 10/10ths (DTC button pressed once), but no problems at 8/10ths. Oil temps were still normal.

After feeding this back to Shiv, he explained that it may be a traction induced limp mode, where the DTC logic was trying to dial boost back to 5psi, but the tune was still trying to hit 11-15psi (or whatever you have it set to).

He gave me a new set of PROcede maps/firmware to try w/ the early stages of his traction control feature, and my low oil temp limp modes went away next track day. I verified that the PROcede dialed boost back to what the ECU wants during traction controlled triggered events, but quickly builds back up to targeted levels once traction is regained, so the net effect is unoticeable (no feeling of being bogged down beyond what traction control was already doing).

Although this possibility doesn't apply to you, since you run w/ traction control OFF, I think it's valuable to share in this thread. We're doing a great job of identifying and discussing all the limp mode inducing causes on the track. I should draw up a fishbone diagram or something For those who don't know what it is, it's a common tool used in problem solving methodologies.

P.S. I bet you had no idea this thread would grow this big. But I guess unlike the other sub-forums on e90post, us track enthusiasts don't feel a need to start new threads for every point of discussion, lol. Otherwise, I may have done so, as this may be worth highlighting in a new thread since it's different from the typical oil and water induced limps we've been focusing on.
Excellent info, thanks for sharing. If you have time to come up with a draft limp mode troubleshooting diagram I'm sure everybody here would appreciate it.

BTW, the "other" tuner just released a max cool alpha feature where they're driving the water pump at 100%, it may help a bit at the track, we'll see.


And yeah, I had no idea this was going to grow into a monster thread, lol.

If you come up with the diagram, we can perhaps sticky it to the first post, along with our track results and overall advice for a cool (literally) track day!
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      06-14-2011, 07:25 PM   #409
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Quote:
Originally Posted by PeterM1 View Post
Excellent info, thanks for sharing. If you have time to come up with a draft limp mode troubleshooting diagram I'm sure everybody here would appreciate it.

BTW, the "other" tuner just released a max cool alpha feature where they're driving the water pump at 100%, it may help a bit at the track, we'll see.


And yeah, I had no idea this was going to grow into a monster thread, lol.

If you come up with the diagram, we can perhaps sticky it to the first post, along with our track results and overall advice for a cool (literally) track day!

Saw the maxcool feature as well. Sounds good in principle but would likely only buy time. Additionally, there are several reports of the pump failing on this car. $300+ part and looks to be about 8 hours in labor. Making it work overtime would be lower on my list.
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      06-14-2011, 07:56 PM   #410
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If you're running 100% distilled with MoCool, I think it means you have to be careful to not have the car sit in ~32F or below weather (freezing point of water)?

Ready to do another coolant flush and was wondering if I can keep this mix during the winter in NorCal (Bay Area). Sometimes it gets down to 30s, but inside garage should still be in the 40s.

Or should I just do a 30/70 coolant / water+2 bottles MoCool mix? Wonder how much difference it is to 100% distilled + 2 bottles MoCool?
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      06-14-2011, 08:11 PM   #411
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This thread is a monster, but in all seriousness, it is the only thread I make a point to review on e90 post. Peter, Either you drive mush more aggressively than I do (very possible) or the AT is the key here. I drove in hotter ambient temps with the STETT OC and had no issues.

Can we add a tune column to the chart, hate to make it bigger but it seems important.
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      06-14-2011, 09:01 PM   #412
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Quote:
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Do not rely on the temperature gauge as the absolute temperature of the system because it is only reading at one specific location and there will be local boiling in other locations.
+1 I wrote and posted pics on this thread of a Friend's E90 M3 which I rode in at the track. It was 86 muggy degrees, and his IND oil temp gauge read 290-300F, while the OEM guage read 270F. The temp probes are obviously in two different locations.

Quote:
Originally Posted by Orb View Post
If chose to run 100% distilled water then you will reduce the boiling point by 7-8 degrees over 50/50 solution and not advisable without a wetting additive. The best comprise is running a solution mix 70/30 with a wetting additive. With this you get addition 6-15 C reduction (feedback from other a few years ago) in coolant temperature and possible more since the wetting agent is effective at reducing localized boiling areas which is a known problem in this engine. The flow rate of the coolant will increase due the decreased viscosity of the coolant as well. The wetting agent is effective with 30/70 but half of what you would see with 100 distilled water.
+1. I'm the only one, it seems, who used 30/70+water wetter.

Quote:
Originally Posted by Orb View Post
If you have auto transmission there are few tips you should consider. Run the transmission in manual mode. Turn traction control completely off. This is big issue with this transmission as the traction control system adds massive amount heat back into the transmission via clutch slippage which ends up back into the coolant system.
This is where I disagree with you. If by manual mode you mean using the paddle shifters, then you are wrong. Using the paddle shifters, causes coolant temps to spike rapidly!! Your typically in the 2-3-4 upshift/downshift, and the clutch packs will get very hot when you do this. This heat is transfered to the trans fluid, and then to the coolant. I leave the tranny in DS mode, and the computer doesn't allow radical downshifts/upshifts, while staying fairly aggressive, and keeps coolant temps low. I don't know how much heat traction control is adding, but remember, we have an open differential. Traction control is the only thing stopping one wheel from spinning faster than the other. Turn off, at your own risk! The car's handling is pretty on point, but TC off in the hands of a novice is dangerous.
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      06-14-2011, 09:32 PM   #413
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Peter, Either you drive mush more aggressively than I do (very possible) or the AT is the key here.

Can we add a tune column to the chart, hate to make it bigger but it seems important.
Let's go with your AT theory for now

Will add the tune column over the next couple of days, will need to dig back into the thread to see what everyone was running.
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      06-14-2011, 09:35 PM   #414
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Quote:
Originally Posted by orionredwing View Post
If you're running 100% distilled with MoCool, I think it means you have to be careful to not have the car sit in ~32F or below weather (freezing point of water)?

Ready to do another coolant flush and was wondering if I can keep this mix during the winter in NorCal (Bay Area). Sometimes it gets down to 30s, but inside garage should still be in the 40s.

Or should I just do a 30/70 coolant / water+2 bottles MoCool mix? Wonder how much difference it is to 100% distilled + 2 bottles MoCool?
Great question. I want to know as well. Why 2 bottles though?
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+1. I'm the only one, it seems, who used 30/70+water wetter.
.
Is that Coolant/Water or Water/Coolant?
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Originally Posted by Turkeybaster115 View Post
This is where I disagree with you. If by manual mode you mean using the paddle shifters, then you are wrong. Using the paddle shifters, causes coolant temps to spike rapidly!! Your typically in the 2-3-4 upshift/downshift, and the clutch packs will get very hot when you do this. This heat is transfered to the trans fluid, and then to the coolant. I leave the tranny in DS mode, and the computer doesn't allow radical downshifts/upshifts, while staying fairly aggressive, and keeps coolant temps low. I don't know how much heat traction control is adding, but remember, we have an open differential. Traction control is the only thing stopping one wheel from spinning faster than the other. Turn off, at your own risk! The car's handling is pretty on point, but TC off in the hands of a novice is dangerous.
Perhaps for those, like me, with a LSD, it does.
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      06-14-2011, 09:50 PM   #415
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This is where I disagree with you. If by manual mode you mean using the paddle shifters, then you are wrong. Using the paddle shifters, causes coolant temps to spike rapidly!! Your typically in the 2-3-4 upshift/downshift, and the clutch packs will get very hot when you do this. This heat is transfered to the trans fluid, and then to the coolant.
What type of tracks do you guys drive that require 2-3-4 shifts? All our tracks in the NE are 3-4 shifts with 5th gear only for the main straight.


Quote:
Originally Posted by Turkeybaster115 View Post
I leave the tranny in DS mode, and the computer doesn't allow radical downshifts/upshifts, while staying fairly aggressive, and keeps coolant temps low. I don't know how much heat traction control is adding, but remember, we have an open differential. Traction control is the only thing stopping one wheel from spinning faster than the other. Turn off, at your own risk! The car's handling is pretty on point, but TC off in the hands of a novice is dangerous.
Does this work? In my 1 or 2 (very early/novice) attempts at leaving the tranny in DS, I found the car consistently at the wrong gear, very frustrating at the track.

DTC should be always on in the beginner/novice class. I would be scared to drive near a novice if he had DTC off. However DTC off is a requirement when you progress to intermediate/advanced, otherwise you'll be frustrated by its constant interference. I find DTC on/DSC Limited (one press) even more annoying, as it will give me the illusion of control but take it away at the moment you need it the most.

Spinning wheels, easy fix: LSD. In retrospect, I wish the LSD had been my first track mod, alas I went for power first, that was a big mistake. At the CCA events, I can tell who doesn't have LSD by simply noticing how fast they bog down while turning.
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      06-14-2011, 10:00 PM   #416
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What type of tracks do you guys drive that require 2-3-4 shifts? All our tracks in the NE are 3-4 shifts with 5th gear only for the main straight.
and how hot do you think your average car's 3rd gear clutch packs get with repeated 3-4 up shifts, and downshifts? Answer= 300-400F.
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      06-14-2011, 10:17 PM   #417
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Quote:
Originally Posted by Turkeybaster115 View Post
+1 I wrote and posted pics on this thread of a Friend's E90 M3 which I rode in at the track. It was 86 muggy degrees, and his IND oil temp gauge read 290-300F, while the OEM guage read 270F. The temp probes are obviously in two different locations.



+1. I'm the only one, it seems, who used 30/70+water wetter.



This is where I disagree with you. If by manual mode you mean using the paddle shifters, then you are wrong. Using the paddle shifters, causes coolant temps to spike rapidly!! Your typically in the 2-3-4 upshift/downshift, and the clutch packs will get very hot when you do this. This heat is transfered to the trans fluid, and then to the coolant. I leave the tranny in DS mode, and the computer doesn't allow radical downshifts/upshifts, while staying fairly aggressive, and keeps coolant temps low. I don't know how much heat traction control is adding, but remember, we have an open differential. Traction control is the only thing stopping one wheel from spinning faster than the other. Turn off, at your own risk! The car's handling is pretty on point, but TC off in the hands of a novice is dangerous.
Hum, I am not sure you understand this but it is simple. First, manual mode has less slip than DS mode as the mechtronics are programmed with greater amount of locking but it is at the cost of smoothness. You are making assumption to some end? There is in BMW document on this site that I posted a few years ago about this transmission.

I think you misunderstood what I wrote. It is only during a traction control event (when the brakes are applied) that a parasitic load is created. If the transmission did not slip (clutch for manuals) then we have a failure or stall the engine.

Although this topic is interesting there are limited options in the end and those should be the focus point. It is well documented that the water jacket between cylinders 5 and 6 have localized boiling problem under high loads. A high performance radiator may not correct this problem. This best approach is using a better heat transfer medium (pure water) and water wetter. A wetting agent is the best possible solution in this case and pure water enhances heat transfer a great deal but at the cost of lowering the boiling point. There some give and take in the fluid properties when you using certain mixture so some experimentation may produce results one may not expect. The next thing is adding a high performance radiator which can improve overall heat reject up to 30% being the same design (size and fitment) just by having a good slat and fin design. Having an auto means your overall heat load is higher which is equal to 2% of the engine load at the crank higher when compared to manual transmission…this is an issue.

Last edited by Orb; 06-14-2011 at 10:37 PM.
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      06-14-2011, 10:57 PM   #418
mid-corner fun
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Drives: e92
Join Date: Jun 2005
Location: NE

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Quote:
Originally Posted by Turkeybaster115 View Post
and how hot do you think your average car's 3rd gear clutch packs get with repeated 3-4 up shifts, and downshifts? Answer= 300-400F.
Sorry, I'd rather sacrifice temps instead of control.

I have no issue with the AT making choices on the highway for me but on the track the car stays on the gear I want it to stay in.
mid-corner fun is offline   United_States
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