340 with edelbrock heads overheating

i already used the ir gun, multiple times. it confirmed engine is getting hot, got 240 at the intake manifold 178 or so on the lower hose. radiator is doing its job. something else is causing the heat.
If you think cooling down only about 25% means the "radiator is doing its job" you are sadly mistaken. I believe you found your problem without knowing it.