1992 Pontiac Sunbird Freezeplug-Coolant blows

Six months ago I was on highway and accelerated rapidly (showing off) but then I heard a loud pop and white smoke behind the car, temp. Gauge rising. I pulled over and shut engine off quick, it was overheating. There was no coolant left at all- it basically exploded. I eventually figured out that the frost/freezeplug had blown from one of the hoses. I replaced it five months ago and drove a little more conservatively, not revving past 4000. There were other issues, but this never came up again until last week. Car is being stored at family farm for winter. Went up to start it and revved a bit, almost immediately the same thing happened. This is a very dangerous problem and I really don't know why it keeps blowing. Please help! If it matters, the current heater core is blown and so is the thermostat- that may have something to do with it?