Reply to "temp gauge"

To calibrate a temp gauge, you'll need a glass thermometer that reads above 220 F. This is stuck in the surge tank with the cap off. Or, use an old cap with a hole drilled thru and RTV the thermometer in place, to allow you to read hotter as water pressure will build up.There are two stock gauges- one reads 0-230, the other, 0-260. This last one is most valuable. There are supposedly two temp senders- the old OEM and the new p/n TS-58. There's a 3rd one that is NOT intended for a gauge; its for an idiot light and does not work hooked to a gauge. Finally, Ford recommended using a 10watt 1/2 ohm resistor initially, then changed to a 5watt 1/2 ohm unit. I suggest using a variable resistor that can be tuned to 0-10 ohms, installed in the gauge line. OK; start the engine & let it idle, with both fans on and the variable resistor set at 5 ohms to start. Compare the dash gauge to the glass thermostat at temps from about 150 to 210 (higher if possible), adjusting the resistor until the gauge and glass thermometer agree.On my '72L, with a new sender and a 0-260 gauge, the most accuracy was NO RESISTOR at all. Finally, after doing all this, turn on your headlights: if the temp reading changes, you may need a 100-amp alternator or a better battery/ground cable, as the extra load for the headlights dropped voltage to your gauge, changing its response. Of course, this is happening at idle so things should be better on the road. Shut things down & let it cool, then solder in a 1%-precision resistor of the value you found to be best for YOUR Pantera, gauge & sender, and you're done.