How to fix a 1987 Toyota supra that over heats?

More than likely your head gasket is bad. Could also be thermostat bad, water pump bad, clogged radiator. Every one with the supra always points to the head gasket. Check your thermostat, Mine was over heating and I replaced it with a low temp thermostat and that worked great. Are yoou losing coolant? check for leaks. Do you notice your water circulating after you turn your car on? If not could be water pump. There are so many other cheaper reasons then just your head gasket. If you are not sure take it to a mechanic, have them look at it. yes it could be your head gasket but why replace that if the solution is a whole lot cheaper.