I have a 77 Vette with a 92, 350 engine in it. My coolant temps only get up to 120 - 130 degrees on the guage. I bought a correct sending unit for the car and the pipe thead is larger than what is in the engine head. I'm not wild on trying to drill out the head for the larger thread while it's on the engine. Corvette Central had a unit that was adjustable to dial in the temp reading. But, it only works if the temp reading is too high. Ae there any options other than drilling the head to accept the stock 77 sending unit? The thermostat is working correctly.
Wayne
Wayne