No need to upgrade the radiator unless you have plans for a high hp goal. SlimFans you can have them run constant so while your driving their still running. Unlike the stock fans that engage and disengage. What antifreeze if any is the car running? I use Redline WaterWetter plus a mixture of antifreeze. Works better with just straight water plus waterwetter but I don't like just running straight water thats just me. Car shouldn't be overheating like that unless the water pump is failing, thermostat is stuck, faulty radiator cap, etc.