The Stovebolt Site Forums The Shop Area Engine Shop temp gauge on a 54-55 head 235

The motor in my 58 is a 54 -55 235 from a car with a pg.
The port in the head for the temp sending unit (gauge)is 3/8" npt.

The 58 motor was 1/2" npt. I found a ford guage temp sending unit that was 1/4". I bushed it to 3/8" and hooked it up.

Cold the needle starts at half way and as the motor warms up it goes off the the scale.

I am thinking if I get a resistor I can make it read lower. Maybe a light bulg in series would confirm this?

I am wondering if there is an electricial guru that can tell me where to start size wise if I where to buy a resistor?


I could not find a TS unit that was 3/8 npt for a guage

THANKS