[racin_ryan]

I have the original gauge sending unit installed in the rear of the intake manifold and an aftermarket mechanical gauge with the sending unit hooked up the the front of the intake. The original gauge is running in the middle/acceptable heat range. The mechanical gauge it saying 230. The car is not overheating, so why is the new gauge registering such a high temp.? The problem started with a new edlebrock intake. Is the gauge bad or install in the wrong position?

[Veronica]

Hello. I think that the first thing that I would is check the temperature in a bunch of places with a laser digital thermometer and see what the actual temperature is. It could be that one, or both, of the gauges have been providing less than accurate information, or it could be that you really do have that much of a variation in temperature.

[buzzboy]

check your new heat guage in boiling water

[Jonk67]

Boiling the gauge is a good test, should show 212* when it starts to boil. You could also switch the gauges to see if they reverse, the stock gauge is notorious for reading wrong.

You can get cheap <$15 IR temp readers at Harbour Freight.
What temp thermostat are you running?
Jon