Temp gauge accuracy

A '72 scamp came with a factory thermostat of 195 degrees F.

Assuming you kept the stock thermostat middle of the gauge should be about 195. I had a '72 Plymouth Satellite and when I had a 160 degree thermostat the gauge stayed close to the cool end of the scale. When I put the correct thermostat in it read in the middle of the scale.

A note about temperatures. Cooler is not better. Engine wear is much greater at 160 than at 195. This is why new cars run at 210 or slightly higher. New cars with higher temps and low expansion pistons now routinely run over 200K miles. This does not mean you should run your Scamp at 210 it wasn't designed to run this hot.

While cooler is not better it is, or can be faster. This is why many hot-rodders run 160 degree thermostats. The lower temp allows for a slightly denser air charge and thus a few free HP, at the expense of longevity.

Regards,

Joe Dokes