Is this overheating?

[MEXICANPT]

Today I went to Toluca, a city about 50 miles north of Mexico City.

The way back to Mexico City is uphill the whole time and very curvy, a Volvo S80 T6 tried to pass me and since I can't have that we started racing, I completely blown him to pieces, but he kept trying so I exited pretty much every curve in 3rd gear and revved it to redline time and time again.

After 15 minutes the temp gauge had gone up to the last line below the red zone, is this area considered overheating? Or is this still in the normal range? Ambient temperature was in the high 30's.

Can anyone comment on this? Any input from the service manual?

I didn't lift until the Volvo was nowhere in my rearview mirror, and when I took it easy the temp gauge went back to the middle in about 45 seconds.

Is there a better kind of antifreeze/coolant I can use?

[SteelBlueGT]

I would consider it overheating but technically I think it is not! Mine has never run so hot but if you didnt loose any coolant and not smell or see smoke you are OK. Check fluid levels and add if you did loose any!! I think you have the extended coolant which is about as good as you can buy for street cars. Evans makes a waterless coolant for race cars which if you keep running yours this hard you may need!

[ptgtcb]

30 deg C or F? Were you running the A/C.
I agree with steelblue and do not feel your fan is comming on correctly! The cooling systems in our newer cars should maintain a steady temperature with very little variation even when your beating on it. Unless our cooling systems just are not up to the task the fan should control the temp and the gauge should not go that high. You will probably need to see the service manual for some sort of test procedure since the PCM controls fan operation and it functions differently with the a/c on or off. A lot of heat comes off the condensor and right into the radiator when it is running and this could pose a problem when running the car hard. Best thing would be to read about how the cooling system on the GT works and get one of techs to check it out.
I would believe there are several fan speeds for certain temp conditions and you should be able to map these by cutting off the flow of air to the radiator and running the engine, I do this by just placing a paper floor mat between the radiator and the condensor and basically making the engine approach overheating and noting the temp and fan speeds as the temp gauge rises with both the gauge and with a hand held infrared temp probe, very useful in finding hot and cold spots in the cooling system.
Good luck in finding what may be wrong, or normal.

[flashbk2]

My thoughts ...if it shows that high on factory gauge you've over-heated no ifs or buts . Probably not bad enough to harm if there's no steam or coolant boil-over. I base my thoughts on running a mechanical gauge on mine in conjunction with the factory . My car in heavy traffic can see 210-215 degrees on mech gauge while factory hasn't budged from mid. Once under motion and air is flowing better and fans come on I'm back to less than 200. Like ptgtcb says it probably was the fan not coming on when it should. I had same problem with my old '01 and I self-isolated it corroded fan relay contacts using the same mech aftermarket set-up .

[MEXICANPT]

I mean Centigrade degrees, sorry.

I was actually running the A/C.

There were no signs of steam or coolant to be seen.

As far as I know the fans are desables at speeds above 44 mph.

But I'll keep looking into it.

Thanks

[Kirby]

If you are going to pull hills like this more than once, you definitely need to do an oil cooler add on, and possibly a trans cooler. Extended hot, high stress running will score your cams. This is why racers tend to use the 20/50wt oil.

If you are not using synthetic trans and hypoid lube....now is the time (Royal Purple, Mobil One, Red Dot are all good).[8)]

[MichaelDay]

Anytime the AC is on, the radiator fan should be on HIGH if the coolant temperature is above 180 F (82.2 C). It should only cut off if the coolant temperature drops below 176 F (80 C).

I try not to run the AC if I really want power or I am really working the engine hard. In the western U.S. most of the long (5+ mile) grades of 6% or more have signs suggesting that you turn your AC off to avoid over heating.