Help diagnosing high water temps at track - Resolved? (not really!)

[BigRussia]

^ Rad and Fan?

[jet_dogg]

In my opinion you didn't change the two most important things that could potentially resolve this issue once and for all.

[BigRussia]

Hey all, finally back with a real update. I got the car to my Indy and picked it up this past weekend.

My Indy diagnosed the issue as a flow problem, both air and coolant. So the 'phase 1' plan was to replace the banged up old condenser w/ new unit, cooling system refresh, and replace the AA underdrive pulleys w stock units.

The condenser was the original factory 17yr old 181k miles unit and pretty beat up (pic below). The cooling system refresh involved brand new OE genuine BMW waterpump, new oem thermostat and both temp sensors, and fresh 90/10 distilled coolant + water wetter. Finally the AA underdrive WP and PS pulleys were replaced with stock units and new belt (ot: strangely my alternator one was still a stock unit) to hopefully help the flow since the 'power' pulleys were slowing down the WP and maybe affecting flow keeping up w/ the temps on track at high RPMs.

Held off on replacing the CSF radiator with a new stock OE one, and still have the mishimoto e-fan that my Indy absolutely hates and was really pushing for me to go to stock mechanical setup with the shrouds and engine ducting.

As before car is perfectly fine on the street, testing and pushing it the water temp needle will still start moving from middle 12o'clock if I dog the car with a bunch of back to back redline pulls, but my Indy thinks it's improved from before when we did the same test before the job. The needle seems to start moving just after 205*F and during normal driving around it seems to sit around 199F with it in the middle 12 o'clock still (during warmup gets to middle around 184-185F). My e-fan currently seems to kick on around 179-181F, might be too low but its not like the fans super strong and makes the temps drop suddenly either so dont know if I need to mess with that. These temp readings are all from the OBD port going to an Ultraguage.

Anyway, I have a track day coming up September 25th to test out if solved or at least improved the issue. I'm hoping water temp needle will stay under or at the 3/4 dot under full send.

If the issue persists and still bad... then back to the shop for 'phase 2' which includes replacing the CSF radiator with a new OE unit and possibly stock mechanical fan setup.

So quick summary of setup and 'factors': car is near full interior with a/c, now has new condenser, removed AA underdrive pulleys (maybe not the main cause but probably wasn't helping the issue), still have CSF radiator and mishimoto e-fan, still have TTFS custom tune.
(have CSF oil cooler as well, but never had oil temp issues, always stay under control and never close to cluster gauge's 255F dot on even the hottest track days. Oh and I grabbed the old t-stat to test it in boiling water, haven't got around to it yet though)


PS. Forgot to mention the old WP looked OK, it seemed like a genuine unit has it had the composite impeller but my Indy commented that it did look alot older than what previous owner had told me (June 2016 ~10,000mi ago), and was good that I replaced it with a genuine OE BMW unit. Did not have any codes relating to the sensors, but figured I have him replace with new oem units while hes already in there doing the cooling system job.

Also leading up to me taking the car to the Indy, I pulled these fault codes. One of them seems related to a bad t-stat, roughly translating to coolant taking too long to warmup to operating temp (also got the related OBD code P0128 for it), so this made my optimistic the t-stat was faulty and the main cause. Let's see after I test the t-stat and do my track day.

[jet_dogg]

Where’s the popcorn

[Estoril]

Awesome, thank you!
Just to clarify, you have a functioning A/C, mechanical fan and stock radiator, right?

Correct. Track-only car driven to/from track.

[GolanM3]

I'm on RE71R, stock calipers, PFC DD rotors, PFC-11 pads exclusively in Instructor group. I run July and August events routinely at 98-100F. Coolant in mid-season is distilled H2O + WW, 50/50 mix early and late season. 12-14 events/year. BMW OE cooling system. (Changing calipers end-of-year to AP/Essex Radi-CALS due to PFC getting out of the performance business and to improve occasional smoking calipers once parked).

Zero temp problems.

Awesome, thank you!
Just to clarify, you have a functioning A/C, mechanical fan and stock radiator, right?

[Estoril]

For those of you that are running stock system, can you provide more details on your car track set up?
- What tires?
- Stock Brakes?
- Running Group? (advanced/intermediate)

I'm running a square setup of 275/35/18 NT01 with BBK in all 4 corners (6 pistons front, 4 in the rear) and running advanced or instructors group. It's clear to me, that relatively speaking, my car will be in a wide open throttle position more than a stock car for obvious reasons (late breaking and early acceleration, almost no traffic), so I wouldn't expect the stock system to keep up with the heat generated during 20min session with ambient temps of 85f or higher. But if you guys see different results under similar conditions, I'd be very interested in your feedback.

I'm on RE71R, stock calipers, PFC DD rotors, PFC-11 pads exclusively in Instructor group. I run July and August events routinely at 98-100F. Coolant in mid-season is distilled H2O + WW, 50/50 mix early and late season. 12-14 events/year. BMW OE cooling system. (Changing calipers end-of-year to AP/Essex Radi-CALS due to PFC getting out of the performance business and to improve occasional smoking calipers once parked).

Zero temp problems.

[GolanM3]

For those of you that are running stock system, can you provide more details on your car track set up?
- What tires?
- Stock Brakes?
- Running Group? (advanced/intermediate)

I'm running a square setup of 275/35/18 NT01 with BBK in all 4 corners (6 pistons front, 4 in the rear) and running advanced or instructors group. It's clear to me, that relatively speaking, my car will be in a wide open throttle position more than a stock car for obvious reasons (late breaking and early acceleration, almost no traffic), so I wouldn't expect the stock system to keep up with the heat generated during 20min session with ambient temps of 85f or higher. But if you guys see different results under similar conditions, I'd be very interested in your feedback.

[Obioban]

So, I feel like I've exhausted all my options at this point. Here's the list of items I've replaced upgraded of the past few weeks:
- T-stat (twice)
- WP
- CSP radiator
- CSP Oil Cooler
- Oil Diverter valve
- New AC condenser
- Fan Clutch
- Added water wetter after several re-flushes
- Took it to the dyno to check tune (seems to be no issues there)

At this point my Indy shop pretty much gave up, telling me maybe I should try a different radiator. I have a track day tomorrow, I'm going to try and remove the AC components and see if I can make it through the day.

Get rid of the water wetter, go to a stock rad and oil cooler, if your water pump doesn’t have a Bmw badge on it replace that, and you should be good to go.

[Rudbari]

Oem cooling system here as well no issues. Try putting clutch fan back and see if if helps the temp .

I recommend you epic tunes . I used there tunes for 4 years and never had any issues .

these problems take time to find and solve

[Nick_P]

So, I feel like I've exhausted all my options at this point. Here's the list of items I've replaced upgraded of the past few weeks:
- T-stat (twice)
- WP
- CSP radiator
- CSP Oil Cooler
- Oil Diverter valve
- New AC condenser
- Fan Clutch
- Added water wetter after several re-flushes
- Took it to the dyno to check tune (seems to be no issues there)

At this point my Indy shop pretty much gave up, telling me maybe I should try a different radiator. I have a track day tomorrow, I'm going to try and remove the AC components and see if I can make it through the day.

I’ve never had any cooling issues with the stock system even on crazy hot days…I would get brand new BMW radiator and oil cooler and you should be good to go

[Estoril]

So, I feel like I've exhausted all my options at this point. Here's the list of items I've replaced upgraded of the past few weeks:
- T-stat (twice)
- WP
- CSP radiator
- CSP Oil Cooler
- Oil Diverter valve
- New AC condenser
- Fan Clutch
- Added water wetter after several re-flushes
- Took it to the dyno to check tune (seems to be no issues there)

At this point my Indy shop pretty much gave up, telling me maybe I should try a different radiator. I have a track day tomorrow, I'm going to try and remove the AC components and see if I can make it through the day.

I'll go with your aftermarket radiator as the cause.

[jet_dogg]

Wait so you have aftermarket rad and oil cooler?

There you go.

[GolanM3]

So, I feel like I've exhausted all my options at this point. Here's the list of items I've replaced upgraded of the past few weeks:
- T-stat (twice)
- WP
- CSP radiator
- CSP Oil Cooler
- Oil Diverter valve
- New AC condenser
- Fan Clutch
- Added water wetter after several re-flushes
- Took it to the dyno to check tune (seems to be no issues there)

At this point my Indy shop pretty much gave up, telling me maybe I should try a different radiator. I have a track day tomorrow, I'm going to try and remove the AC components and see if I can make it through the day.

[sapote]

It makes me wonder if the algorithm in recaptures box displays the readings a bit low. I think I'll run the secret menu next time I'm at the track and compare the OBC's value vs. recapture's value.

I see no reason for the Recapture box to alter the captured temperature data. I bet the hidden display on the dash shows the same.