What happens when an engine runs too cool

[priderocks]

My 383 is a fresh rebuild, pretty much stock cam, with original recored 22 inch radiator in my Challenger. I have a couple of pints of "Water Wetter" in it. The car never, I mean never gets above 160 degrees. It also doesn't run real well between idle and 2000 rpm. My question is, can a car run too cool? The engine setup is stock- exhaust manifolds, heat stove with tube, etc. I'm just wondering if my "flat spot" is related to the engine running cool.

[Moparal]

Did you degree the cam?   160 isn't going to make you run bad

[TommySS]

What T-stat are you running?

[73Chally]

Are you going strictly by the gauge, and if so are you sure of its accuracy?  If so, then you might want to buy a 180 Thermostat, put it on, and see if the temp goes up.

[Chryco Psycho]

I would switch to a 180* thermostat, I would rather have it run on the cool side but it may atomize fuel better at 180*, it could cause a flat spot off idle

[Roppa440]

I always use a 180 degree thermostat.

Modern engines are often designed to run hotter than that as it helps with emissions and reduces engine wear.

Drag racers like to run a cooler 160 degrees because they claim the engine will make more power at that temp. But manufacturer tests show engine wear is much greater at 160 compared to 180.

[femtnmax]

I have a Snap On thermometer from my days as a dealership line mechanic.  It will tell you the TRUE temperature.   Just take off the radiator cap and say AHHH    Some NEW t-stats are bad.  I also agree with all posts above, especially the one about engine wear.

[Super Blue 72]

For some odd reason I seem to remember an article from the 80's saying that SB Mopars like to run at 185 degrees F. 

I tried a few different thermostats back then and it seemed like the 180ish temp thermostat made the car run better, at least in my case on a 318.

[wagesofsin]

internal combustion engines that are water cooled are designed to run at a set degree to optimise expansion of sealing parts , and to maximise efficiancy . to cool is not 160. 180 would be optimum, but you arent doing any damage at all by running there. is your t-stat actually functioning?
it may be defective and open all the time(ive seen stupider things happen)
do your hoses actually pressurise when the car is hot?
it is a sealed cooling system, thus under pressure.
got heat?

just some thoughts, im no expert by any stretch, but i love a good mystery.

[cudabob496]

Some engines make more power with a 160 thermostat, and some with a 180 degree. With aluminum heads, a 180 worked better for me on my 496 Cuda.