180 deg. Thermostat

[JAW]

I called about getting my coolant flushed and I asked how much to put in a new thermostat. He went on about how if I put in a lower temp. thermostat that it was confuse the computer because it would run so much cooler, make it run rich, and burn a bunch more fuel. So what is the real deal here? I know most of you all have one. Any problems?

[openclasspro]

didn't add any more power too it-now that it's cooler out- i get a 1740 code-engine doesn't heat up to operating range quick enough-and also my od flutters around + and - 300rpms- fellow ram owner had same prob- dealer said it was do to the stat and pcm was confusing the tc on locking and unlocking-they put 195 back in and problem went away- if youare gonna do a pcm - change it- if not i wouldn't bother-my .02$-phil

[Kevin_Rants]

I disagree, I've run a Robert Shaw 180 in my 95 Dak and 99 Durango, no problems. Most of the Dak guys run them also.

[Old guy]

notice that his truck is a 2001. JAW has a '99 like yours and mine, Kevin. The 180 will work just fine. I even ran a 160 in mine last winter and didn't get any codes. I went back to the 180 because I almost froze my butt off. Cab took too long to warm up with a 160. Computer and control systems are different evidently. There is no horse power gain by going to the 180 but it works well with my other modifications. Besides I am old and 180 was normal when I learned how to drive. 195 makes me nervous.

[2001 Durango R/T]

I was also told that if you put in the 180, the car won't pass the smog check as easily as the cat doesn't get hot enough. BS or not, who knows. I haven't heard of any significant gains with it, so I think that I would rather go with the IAT adjuster so that you can put it back to stock setting when you get your truck smogged.

[Old guy]

[2001 Durango R/T]

Originally posted by Old guy

You know, every once and a while someone says something that's really in tune with the way we should do things! *LOL*

[JAW]

It doesn't sound like the lower thermostat will do anything to performance unless you have a computer upgrade. I have also heard that emmisions could be a problem. Is there really any performance increase and why?

[Old guy]

I'll admit up front that people have said that the 180 doesn't add any performance including Kenne Bell that has put it on his dyno. I am hard headed sometimes. I still believe that lowering the block temperature 15 degrees has to have an effect on the incoming air charge and everyone knows that a cooler charge will yield better performance. I use 180 on all my vehicles.
As far as the polution testing goes, there is no sniff test in my area yet. My guess is that engine temp could only have an effect on the converter during initial warm up. With exhaust gases coming from the engine, the cat should get up to normal operating temp regardless of engine temp.

Note: This is my own line of thinking and if anyone disagrees, just have at it. You won't flame me up.

[JAW]

It would make sense that by lowering the engine temperature that you could put a denser charge into the ignition chamber (add more fuel in the same given space). The problem seems to me that the thermodynamic efficiency of an engine goes down as the temperature difference of the cycle goes down (the difference between the ambient temperature and the temperature in the combustion chamber). I believe that is why this could have an effect on the emmisions. As for performance, does anyone know that it does help? Is this just a useful additioin for the computer upgrade? What about the box every is using?

[Old guy]

You are correct in the thermal effeciency of the engine. That is why the corporations switched to 195 from 180 a few years ago. With the higher effeciency the emissions go down and MPG goes up. In theory, effeciency and performance would go hand in hand but in practice the engine runs better for drag racing purposes if it is colder than optimum effeciency. I'm talking way over my head and repeating things I have been told by engineers. Don't ask me for a more technical explanation because my pea sized brain will probably melt and run out my ears.

[driftin4]

I am running the 160 deg Hypertech Power Stat in my 5.9 with Water Wetter and have no problems.
Well, I would prefer a little more heat now that the temp is dipping below freezing.
It did get rid of my ping problem though.