Does radiator additive as super cool work?
 

I have a 2000 corvette which sometimes the temperqture runs to 210 in summer time traffic. Does anyone have experience with a radiator additive as super cool. Is it harmful to engine?

I'm not familiar with that specific product, but it's probably along the lines of a "water surfactant". REDLINE "Water Wetter" is a common water surfactant. If you're not familiar with that terminology, do a little research using those keywords.

FWIW, 210 degrees is not uncommon in summer traffic. Your secondary fan doesn't even come on until 226 degrees if I remember correctly. The LSx motors are engineered to run at higher temperatures. These are not the sbc that Grampa drove.

You do not have a problem.

210 is perfectly normal. Straight water is wonderful for keeping down temps but it is not good for the pump. Part of the coolants job is to lubricate the pump and cut down on corrosion. That is where the Water Wetter comes into play. When I raced motorcyles, you could not use coolant in the bike because it woudl cause the track to get slippery in the event of a crash. The water wetter plus deionized water is all that was allowed. An added benefit was there would be maybe a 10 degree difference in temps as well.

Our Vettes are bottom breathers. They suck up a huge amount of crap from the road that will eventuially clog up a major portion of the condensor fins blocking air flow to the radiator. Before you mess with addatives, jack up the front of the car and clean out the intake area. You can use a vacum with a long crevice tool to get to the top portions. The best way to clean is to use compressed air and blow it out from behind using an angle tool, but that takes some disassembly. Search, there are several threads on the process.

If this temp is a bother you can have the fans programmed to come on sooner than the stock temperature program. I did this.