Hey everyone,

I did a my 2nd HPDE day with my Mach 1 yesterday - it was at Watkins Glen and it was mid 90s most of the day.

In my 3rd session, I was pushing pretty good and my cylinder head temp reading got up to 245F. I did a cool down lap and it dropped back down to about 220, so I picked the pace back up. It went back up to 245 in a little over 1/2 lap. Car was running fine, no warning lights or anything. But there was only a couple laps left so just to be safe I pitted and let the car cool down. The car was back down to 220 just from making a few slow laps around the paddock. Trans and diff temps were fine the whole time.

I was concerned because I used to race about 20 years ago and we would start to worry if *water* temps started creeping up above 235-240 (we'd like to run at about 220). But I honestly don't know how much the cyl temp reading corelates to the actual water temps?

So I'm just wondering - what's a decent range for the car specifically for the cyl head temp reading for a track day? When should I start being concerned and consider pulling off?

(on a side note, its a little annoying that the "gauges" display just shows a dial and not actual numbers, which would be more relevant for a "track capable" car)

Thanks!

I used to look carefully at temperatures in my track cars but I eventually realized that "there's a computer for that" that takes care of the engine and drivetrain and if it gets too hot, it'll cut power to protect the equipment.

These days the only thing I monitor on my dash display is tire pressures. The computers do the rest.

I try not to run over 235 CHT which if i hit, i start to back off. I think most would consider over that or at least over 240+ too hot. Also note that the hottest cylinder is typically #8 and it will be hotter than what the sensor reads.

Believe that past 245F is where the computer starts to pull power and shut off AC if it's on, at least that's been my experience.

Cooler is better so there's nothing wrong with what you did, but on my Dark Horse I pretty much let the computer take care of it. So long as the AC is off I've been seeing lower temps than that, even on days pushing 100F. With the AC on it'll be around 240F.

You can pull more data from the OBD2. Unfortunately a lot is calculated rather than directly read. The more you mod the system the less accurate it becomes.
You can see the water temp follow the rpm on long pulls. If you can stay on track and out of the way, short shift and cruise at speed to get max cooling effect.
"track capable" is a debatable term, quick yes, in short squirts, its a road car that needs TLC, not tender loving care, Truck Loads of Cash to be an endurance racer. Ask my bank balance.