I have a primarily stock low compresion 440 In my 70 Challenger. It was a 74 motor. Stock bottom end. The only modifications are milled heads and a slightly hotter cam. Stock exhaust and intake. The car was an original 318 A/C 3 speed car with the heavy duty cooling system. I'm using the factory radiator that came with the car. It was boiled out and tested. Problem is I'm running the factory non ralley dash. On hot days the gauge runs just below the hot line. (within the normal range. But I meen it's right next to the line. It seems to be worse on the highway than around town. Since there are no numbers on the guages does anyone know about what temp I'm running at. Is this normal or do I need a larger radiator. I was tole this was the biggest one for the challenger. It's never overheated, but once in a while it will spit out a little coolant after being shut down. Any help would be greatly appreiciated