On my old civic hatchback, it had a half size radiator and it over heated during track days. So I made a blockoff where the condenser would go out of cardboard. On my way to the next raceday, on the freeway. It smelt like something was burning but I figured it was maybe something close to the freeway that I was passing by lol maybe 10 minutes into this. I noticed fire coming out of the back of my car. I thought to myself. "wtf, there's no way I just say that" so I carried on lol, then I saw a ball of fire come out of the hood right in front of me! HOLY SHIT, cars on fire!!! Immediately pull over, manage to pop my hood using my shirt (it was hot as hell) to see my stupid ass ghetto blockoff idea resting against the headers and on fire!!! DEAR LAWD ITS FYRE! I had no water, so I went to grab what I thought was dirt and BAM!!! Fire got way worse. Turns out it was dry branches and such! I thought maybe I should open the radiator cap and run for dear life so that the hot coolant wouldn't get me too bad ( had already been driving for over an hour), I pop it and almost dove out of the way just to find out that the system wasn't full and didn't have the pressure to explode LOL FML, thought to myself "there goes this car, it's done for" when I see a piece of tire on the road that I ended up using to get the burning remains off, then pushed the car away from it.
It was so scary lol so no more cardboard condenser blockoffs for me. And always carry a gallon of water at hand. Will have a fire extinguisher soon!