Trackday cooling

[wxywb021254]

Hello guys, here i come again...

 

I did a track day with my 420 duratec the week before and I am so happy with how the car performed! Super fun and sliding around 

 

But I do have a question: in the afternoon (ambient temp ~70-75F), my coolant temp slowly creeped up to ~105C range at the end of the session. In the morning, no issue at all the car can do whole session at 100C. I am running zetec coolant (yes, not water since my 7 is more of a street car). Is it normal that the cooling cannot keep up at this low ambient temp? Any improvement I can do?

 

BTW, here is a video from my track day!

 

 

[KnifeySpoony]

My 420R runs cooler (about 200F while on track, but temps go higher when idling in pits after coming off, up to 208, then the fan kicks on), but I have dry sump with oil cooler. What is your water/oil cooling setup like?

 

edit: random question: does your car have LSD option or is it open diff? Just curious to know based on the ease in power oversteer you were getting. I'd assume it was LSD.

Edited March 10, 2022 by KnifeySpoony

[John B]

FYI - Evans Waterless Coolant is a great improvement for systems that are cooling challenged. It's boiling point is 375 degrees. It's when the coolant boils over that things get really ugly.

 

https://www.evanscoolant.com/how-it-works/benefits/no-overheating/#:~:text=Evans waterless coolants have a,times%2C enabling consistently effective cooling.

 

Edited March 9, 2022 by John B

[jeffs]

Depends on how many slower cars you get stuck behind

 

My r500 Duratec ran about 90C on the track, but I'll see 100-105C on the streets if I'm stuck in traffic.  My fan isn't programmed to kick in until 104 or 105C.  

[Croc]

Thermostat should be opening at either 82C or 90C depending on which thermostat Caterham supplied with the 420 Duratec kit.  The ECU was programmed to be match fan activation with thermostat.  In theory at least.  

 

I also think you should run cooler on track as you have a ton of airflow through the radiator, even allowing for the higher revs on the engine.  Street driving tends to run hotter.  

 

So do you have a sticky thermostat?  You can pull it and test it in hot water to see if it opens at the right temperature.  

 

Great track day video - you were having a lot of fun!

 

 

[sf4018]

Great video and driving skills! The Caterham ECU switches the fan on at 105C and off at 101C, it runs hot, so those temps seem within range.

[wxywb021254]

Thanks guys! I did have a lot of fun and got to know some other caterham owners. Yes, during street driving the fan and temp behaves just like you said, turning on at 105 and then temp goes down. The part I don't like that much is on track, the car is going to or a bit above 105 since I would think on track, fan is not the major source for cooling. At least that's what usually how my track Miata do. But agreed, maybe it's just how the different cars cool.

 

Btw, my car has dry sump and oil cooler. Sadly no ac though😂

[Vovchandr]

Subscribing to follow others with cooling woes...

 

I tend to run hot or overheat at idle nowadays but I've been fine on the track and while moving in general. 

 

As a matter a fact while sitting in queue to get on the track last time I started to get hot and cooled down when got on the track and stared moving. 

 

I have a pending water rail order but I'm not sure it would resolve my problems. 

 

Zetec.  

[wxywb021254]

It’s a detour of the thread. But today I drive my Miata track/race car after I drove my 7 on track last time… I never thought my Miata was not balanced until now…