Autocross - overheat?

[Rexracer]

At Packwood talking to Peter Ling, he said he use to rune a Fiesta, but was getting overheating/limp mode issues mid run on hot days. I thought that was odd as I havent had any issues. Well later on I finished a run and noticed I was at max "normal" range, on a low 60s day. We were dual driving so more runs, but still on a cool day this makes me nervous. I was running the heater and leaving the car running to let the radiator do its job between runs.

So A) are others overheating at AX?
B) is there a solution?
C) are we really not allowed to swap radiators in HS?

 

[SrsBsns]

I'm sure it's common. Cooling system on this car is a well known weak point.

If you can't swap the radiator, I'm not sure if there's a solution. That seems to be the universal solution to everyone's cooling problems.

I don't AX, but was dealing with overheating when driving mountain roads and even got hot in stop-and-go. A Mountune radiator has solved all my problems.

 

[M-Sport fan]

If H/Street rules forbid an aftermarket radiator (as I believe they do), I would go to at least an 80% water/20% coolant mix (if not a 90% water/10% coolant mix), add one of the anti-cavitation additives, and seal up the fan shroud as much as possible with some high temp foam.

Are you allowed to spray the radiator and intercooler with cold water between runs in H/Street, or does the draconian SCCA even disallow that?!?

 

[SteveS]

Back in the 1980s when I was autocrossing the Indian can to spray water on the radiator was de rigueur between runs. Even in stock class.

The other thing I never see anyone talk about is that when you start having rising temps/overheating when you didn't have trouble before, backflushing the radiator would often cure it.

 

[Rexracer]

I thought my question seemed familiar, this was just discussed, sorry for bringing it up again!
https://www.fiestastforum.com/threads/overheating-issue-during-autocross.24295/

 

[The_Ryan]

with stock radiator I've gone into limp a couple times but usually my coolant gets to 230-235 by the end of a run. I ran with the heat on full blast, and leave the hood open and the engine running between runs. The three other FiSTs or so that I've seen all have overheated and limped

 

[kivnul]

A bigger radiator is not allowed until Street Touring class. Stock class you can swap out the thermostat though. I autocross (a couple times dual driver) and it can get into the 90's and I have never had a heating issue. I do think the radiators on these cars are hit and miss, maybe some of them are defective and just plain do not cool well. Having said that, I want to track my car so I went ahead and upgraded to a Mountune radiator anyways.

 

[faust]

. . . I do think the radiators on these cars are hit and miss, maybe some of them are defective and just plain do not cool well. . .

That makes sense. I've done a bunch of autox runs with temps in the 90s, and never seen the temp gauge go beyond the normal range. (stock '15 with 50k miles)

 

[CSM]

Swap out for the newer thermostat (if it's a 14 or 15 model year), run distilled water, and keep the heat on full blast. That's about all you can do in HS