Drain the radiator on pop the top hose off the thermostat housing and see what you have. If there is no thermostat I’d recommend putting one in. Stock temp is usually around ~195. I like to run 180* on my stock/drivers. 160* on anything built to beat on. 13lb cap is good.
if you dont see a stat...most likely theres an issue with summer temps that the cooling system cant handle....ie...parts of rad pluged....fan bleeding...or collapsing lower hose.....all easy to deal with..good luck..