360 overheating -please help

i have a 1973 dart swinger -I bought off Ebay the guy said it has J heads and he did a lot of work on them ?? who knows if this is the truth the motor seems strong though,since recieving the car the temp would not stay below 230 it would rise slowly the engine combo is 1978 360 9.5 to 1 comp cam Hyd
.510 duration at .50 intake 240 exhaust 246 -lobe lift .3380 Exh .3400
lobe seperation 110.0 dont know what pistons or any internals -airgap intake 1" spacer , headers,flowmaster,aluminum radiator,16" electric fan 2150 ,the stock fan is gone,cfm ,edelbrock hi volume water pump,no thermostat, holley HP 750 DP,TCI super street fighter 3500 stahl 8/3/4 with 4.10 posi,904 built , on the highway cruising at 50 mph temp seem ok anywhere in town the temp guage rises like flood water i used an infa red heat guage it was rising up to 230 and beyond if i let it. the car has not boiled over but when i see the guage rising i turn it off ,ive had the car for 1 year sunk a small fortune in it and probably only have driven it for 1 total hr due to getting hot i dont want to blow it up,i am not mechancally inclined but i do listen.