Does switching to a cooler stat REALLY hurt MPG?
 

I've heard a discussion on a local radio station recently where a mechanic stated that in todays modern, hotter running engines it was better to stick with the more common 195 degree OE temp stat to maintain better MPG and emission figures than switching to a cooler operating t-stat.

I was wondering if there is any truth to this notion? Has anyone felt that by switching to a cooler 180 stat their MPG or emission numbers have suffered, even slightly? It seems that by using the cooler running 180 or a hotter OE 195 there are good points and bad points to be made for each argument.

Look at my sig. I can still pull 29 mpg on the freeway. With the bonneville at least (or any other L27, L36, or L67 powered car) it will not hurt your mileage even a LITTLE bit. NO change whatsoever.

They were probably talking about rice. You have to cook rice at the proper temperature.

I just returned from a 2800 mile round trip. I have the 180 degree thermostat and my average for the trip was 29.7 with one tank hitting 30.3. I doubt I have hurt the mileage at all. :wink:

DrJay said that it allows more fuel to be available to your engine.....somehow dunno. That would cause you to think that you are using more gas because you can accelerate faster.