GM-GMC: Gage Indicates High Operating Temps, gage calibration, core radiator

Question
Thank you for your recent reply to a related question. I am taking your advice regarding the 180 thermostat and the synthetic oil (for my rebuilt 350...83 chev pu). However, you mentioned gage calibration in your answer. I am now wondering if the change from the factory installed 305 to the rebuilt 350, using the factory dash mounted gage, could be a problem. I was told that the sending unit is standard on all small blocks. What do you think?  Also, my truck has the smaller OEM ("2 core") radiator. Would the larger "3 core" produce the desired result?

Answer
Go to www.rockauto.com, look through the different year engines, and see what gauge senders they use.

A bigger radiator is usually a better idea, but the thermostat is responsible for maintaining engine temperature.  The radiator simply gets rid of the heat and a bigger radiator will do a better job of getting rid of heat on a hot day or when the engine is under a high load.