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Discussion Starter · #1 ·
I was racing this last weekend(road course) and my car on the second to last session of the day overheated and went into limp mode on the last lap of the session. It cooled down and it ran fine, the next session I got about 3/4 through and it started to climb above 220 and creep up to 250. So I shifted earlier and eased back a bit and it held at 220.

Each session is around 20 minutes, this is the second year I have raced it and never had this issue before but this weekend the heat didn't let up. It was 97 degrees all day and due to gearing I am between 4-6K rpm's for about 2/3's of the track. I took the engine covers off and that seemed to help a bit but if pushed it would still get hotter. Driving home, my out and checkered flag lap when I was only going about 60% the temp didn't move a bit. Anyone else run into this or experience this when racing their vehicle? If so what did you do to fix it?

I am thinking about flushing the system and putting a new T-stat in there but I don't know if either of those will help. The stat seems to be working and the fluid looked fine and the reservoir was full.
 

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Do you have any cooling mods like a bigger pump, upgraded Heat Exchanger. etc...?
 

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Discussion Starter · #4 ·
Nope, I haven't done any of those mods yet because I was not sure how long I would be circuit racing the car. And quite honestly it hasn't had any issues thus far. I am stock except for suspension/brakes, cut out and was running slicks. I am open to hear experiences on heat exchangers if that will help. I will probably run this another season until I get my comp license and get a dedicated track car.
 

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How's your diff temp? You should be adding a cooler to that and changing the oil frequently I hope....either that, or swap it out with an aftermarket unit.
 

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Each session is around 20 minutes, this is the second year I have raced it and never had this issue before but this weekend the heat didn't let up. It was 97 degrees all day and due to gearing I am between 4-6K rpm's for about 2/3's of the track.

I am thinking about flushing the system and putting a new T-stat in there but I don't know if either of those will help. The stat seems to be working and the fluid looked fine and the reservoir was full.

What may be happening is that you may be getting to the limits of what the stock cooling system can handle. All things equal, what the system can handle at 92 may be more than it can handle at 97. That or your stock water pump may be weakening some. Flushing and a new stat should not hurt but may not help, especially if the problem is just that your demands are at the edge of the capabilities of the stock system. Your problem might go away when the conditions improve.
 
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Do some research on Heat Exchangers. There are tons of options and opinions on them. I recommend the Pierberg pump for an upgrade. Several vendors carry them.
 
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Discussion Starter · #8 ·
How's your diff temp? You should be adding a cooler to that and changing the oil frequently I hope....either that, or swap it out with an aftermarket unit.
I change the diff fluid and brake fluid before every race weekend. I am running royal purple in there and I haven't had any issues what so ever with it. If I do plan to do this for a couple more season with this car then I will definitely be looking into a diff cooler. I have read the threads where people get issues with that. One issue at a time.
 

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Discussion Starter · #9 ·
What may be happening is that you may be getting to the limits of what the stock cooling system can handle. All things equal, what the system can handle at 92 may be more than it can handle at 97. That or your stock water pump may be weakening some. Flushing and a new stat should not hurt but may not help, especially if the problem is just that your demands are at the edge of the capabilities of the stock system. Your problem might go away when the conditions improve.
I think you are right, the beginning of the day when it was cooler I was running it hard and it didn't move above 220 with the ambient temp outside at 71. One of the instructors even said that they were surprised I wasn't overheating, some other cars had some issues also because it was extremely hot out.

I think I might flush the fluid and try a new T-stat, I don't want to go throwing parts at the problem but those are maintenance items. The shitty thing, well good I guess.......is the next race is in October so it won't be that hot. I won't know if that did anything until next year lol.
 

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Check for leaks. The clamp on my lower radiator hose rusted out and fell apart. The overflow reservoir remained full but the car had no coolant. Don't know how long I had been driving it that way, but one day going up the hill to my house it went in to limp mode and I discovered the problem.

I've flogged the shit out of my 14 Coupe on a local road course in 90º weather and the only thing that cooked were my brakes. F'in car is just too heavy...
 

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Def
Check for leaks. The clamp on my lower radiator hose rusted out and fell apart. The overflow reservoir remained full but the car had no coolant. Don't know how long I had been driving it that way, but one day going up the hill to my house it went in to limp mode and I discovered the problem.

I've flogged the shit out of my 14 Coupe on a local road course in 90º weather and the only thing that cooked were my brakes. F'in car is just too heavy...
Definitely heavy. We need to reboot a weight saving thread to explore new ideas
 

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Discussion Starter · #12 ·
Check for leaks. The clamp on my lower radiator hose rusted out and fell apart. The overflow reservoir remained full but the car had no coolant. Don't know how long I had been driving it that way, but one day going up the hill to my house it went in to limp mode and I discovered the problem.

I've flogged the shit out of my 14 Coupe on a local road course in 90º weather and the only thing that cooked were my brakes. F'in car is just too heavy...
I checked and all lines, hoses and clamps are in place. There was no fluid leaking at the track, the track officials would have black flagged me quickly. I wish it was something this easy, and cheap lol.

The brakes are tricky, I blew my brakes and boiled my fluid early this year. I had Motul 600 in it too. It is an exciting experience driving a car with no brakes. The problem wasn't really the brakes or the weight, well the weight was a factor but the other parts that worked with the brakes. I had some meh tires on so the brakes were great but I had to stay on them longer because the traction on the tires would break well before threshold braking occurred. So my whole braking zone had to be extended about 9ft. and I was basically trail braking at least half the braking zone. I put some good rubber on, some DTC70 pads, proper fluid and rotors and haven't had a single brake issue, not even fade this last weekend. And we have two straights on the course where I had to slow down from 128-76mph and 105-61mph.

Without the proper set up though, you are right. The brakes are great but trying to stop 4000lbs without proper traction or rubber you are going to burn your brakes.
 

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