Tracking car hard in hot climate

[heinzboehmer]

I run no mechanical fan and stock everything else. Cooling system is refreshed, but I even run 60/40 mix of distilled water and BMW coolant, so nothing fancy to try to keep temps down. Been to hot Thunderhill days (90+ F) and my car had zero issues. Water temps have always stayed rock solid in the middle and the highest I've seen oil temps get is about 240 F.

Just make sure your cooling system is refreshed and the air passages in all the radiators (coolant, oil and AC) are free of debris. As stated above, stock cooling works very well.

[Koolsilver]

To give you some perspective I was at Thunderhill last Friday and it was about mid 70s. I wasn’t paying close attention but I never saw my coolant go above the middle and I saw oil get to around 250. I wasn’t fully pushing it because it was the first event out with the car. I have a stock cooling system with silicone pipes. I recently refreshed all the pipes, pump, fan clutch, but kept the original radiator and oil cooler. I am running about 50/50 water/coolant with water wetter added.

[Driver407]

Totally a chance i am over thinking this and the oem can suffice. Read so many differing opinions on the cooling.
Just trying to prevent any wasted track time for my first event if i can do a few fixes beforehand. Maybe i should just bite the bullet and do an event fully stock and see where i am?

[EthanolTurbo]

I don't think you need the upgraded radiator, honestly. The stock one is really good. And I encountered weird heat issues with my CSF rad where it would spike temps under heavy load especially uphill when it's 100F+. Maybe just replace your old stock one with a fresh rad and update anything else.

[Driver407]

Hi all,

First post here on the forum.

Recently bought an E46 M3 as my dedicated track car. Have been tracking my F80 M3 daily the last two years (~20 events) with zero worries in regards to cooling. However i know i am going to need to refresh some if not all of the e46 cooling setup.

I track in California and my closest spot is Thunderhill. Most sessions are 25~ minutes. Some organizations run open pit sessions that can be 45 minutes.
In the next couple months it will be 100-110 degrees out at track days. Currently gets to around 80.

Starting to plan out what things should be done around cooling for e46.
I would really like to get the e46 to the same point as my f80 where i don't even have to worry about how hot it is.

Part of me wants to address all of the items below in one big garage session. Part of me want to do just a few of them to get me to the track for my first few events and not have to do it all at once.

1) Upgraded Oil Cooler (looking at CSF)
2) Upgraded Radiator (looking at CSF)
3) Distilled water/waterwetter track combo upgrade (vs standard 50 water/50 coolant)
4) New 16" fan and relay (hear oem fan can nuke?)
5) Performance thermostat
6) Upgraded waterpump (metal fin)
*If i am missing any other popular cooling items from my list, let me know

TL DR. My main question here:
1) Out of the upgrades above. If i just want to be able to make it through my sessions and not have to stop and cool within a few laps.
Which should i do right away vs can be put off for a few more events and may not be as drastic an improvment? Or is this a much larger e46 issue where i am not going to solve it without doing all of them?

My current thoughts are the oil cooler, radiator, water wetter for my first few events? Rest can come as need be? As time/money persist?
Would those three upgrades set me up for really hard 25 minute sessions?