Radiator leak

[Cbitz23]

So I was hauling ass last night and this camaro rs wanted to race. I tried so hard not to but gave in. Afterwards we met at a gas station and I revved for him he revved for me. After i revved. Smoke was coming out of the hood.  Popped hood and BAM. Green liquid was EVERYWHERE. got home and car didn't overheat or come close. The tank was dry as bone and this morning I put water in and drove to a shop a mile down the road. Car ran fine and the water was still same level and temp was fine. Curious as to what caused it. Possible head gasket blown? Or hopefully a hose came loose? Didn't feel like doing it myself so took to a shop but yet to hear from them today 

[studegary]

Hopefully, something simple and inexpensive like a radiator cap pressure failure.  

[WayneC]

...or a sticky thermostat.

[Gunslinger]

When you drove a mile this morning with a cold engine the pressure probably didn't have time to build up and the temperature didn't have a chance to get to normal, much less overheat.  You should have the entire system pressure tested and see if can hold pressure.  If it can't the leak should be apparent.  Make sure the radiator cap is pressure tested as well...it can be bad.  As already mentioned the thermostat could be sticking and once it heated up the coolant could have gone out the overflow.  

If you need a thermostat, specify a fail-safe type that should go bad, it goes bad in the open position so it can't make the engine overheat.  

Another thing to check is the lower radiator hose.  If its internal spring has rusted away it can collapse under high rpm vacuum and make for a blockage which causes an overheat condition and coolant goes out the overflow.  At low speeds it will act normally.  

Depending on how old the hoses and belts are in the car, it might not be a bad idea to flush the radiator and block and replace all the hoses and belts.  That's also assuming a pressure test reveals no other problem.

[Cbitz23]

Thanks everyone. At work right now but pick my car up in 2 hours during lunch. They fixed it for $90. They left a message don't know what the problem was until I get to the shop. And it's a very well trusted shop in my area so hopefully all is well.