E46 M3 overheating at the track?

[singletrack1]

Anyone out there overheating their E46 M3 at the track? If so, any solutions?

I have 3 customers that are overheating out at the track. 1 had the dealer replace the fan clutch, thermostat, and the water pump, but he overheated at the track this weekend about 10-15 minutes into the session.

The ambient temp was around 95 degrees. The cars are fairly new with about 20K to 40K miles and they have stock motors.

TIA

Bill Kim

[M52 POWER!]

Try water wetter additive.

[odortiz]

try 1 part antifreeze and 2 parts water as opposed to 50-50. also the water wetter.

[Steve J.]

I'd suggest not to run Antifreeze at the track, its a safety hazard.

[maranelloman]

short shift...

[rmani]

haven't really heard of e46 m3s having overheating issues, but i'd try what a couple of the others guys said. Use more water than coolant in the mixture, as this should help.

[JClark]

I'd suggest not to run Antifreeze at the track, its a safety hazard.

Steve- I've heard you should run at minimum 10% coolant because it protects the cooling system internals from corrosion. Is that correct or no?

[dak656]

If you have a pure track car, please please please do not run antifreeze. I don't know if you've ever got some on your shoe or something, but etylene glycol is F slippery...

You can get rust inhibitor to run in the cooling system, we use NAPA stuff in the Champ Cars... it's white, milky-looking stuff... I think it's NAPA Number 14 or something... not sure, and NAPA's website isn't working right now.

edit: working now, it's the MAC's radiator rust prevention additive.

[HBpredhunter]

yes running anti freeze in a race car is a no no.
always pure water. DISTILLED at that. with water wetter.
just do a flush when you wanna run at the track... pretty easy.

[332 RustBucket]

I have never heard from a e46 owner that they have had problems.

[jmott]

I have never heard from a e46 owner that they have had problems.

some places are hotter than others, and some drivers are more agressive than others.

I can make every single fluid in a z06 corvette overheat in 5 laps at texas world speedway, while many drivers say they never have any problems, heh.

[Vince S.]

95F seems ok for a track day. I have taken my e46 325 to places where 110F was ambient. Track temp as high as 140F.

Any idea what oil temp they were running when they over-heated?

Also, on the subject of overheating, I know some folks refer to overheating as the water temp needle touching or in the red zone, while others refer to as soon as the needle starts to climb from the middle position. What's the consensus here?

[332 RustBucket]

some places are hotter than others, and some drivers are more agressive than others.

I can make every single fluid in a z06 corvette overheat in 5 laps at texas world speedway, while many drivers say they never have any problems, heh.

I agree with you just that several of the people who run the e46 m3 are very good drivers (not pro) and run in 90+ temps. Maybe they just know how to drive

[srmatherne]

I seem to remember reading that Evosport had to underdrive the water pump on their car as the stock ratio caused cavitation at high RPMs...note that Evosport also sells pulleys. Otherwise you might have them give the BMW motorsports thermostat a try.