I'm about to head over to the parts store to get and abs sensor and while I was there I was thinking about going back to my 180 degree thermostat. How much of an improvement would I see?

 

Improvement in what? You won't see any noticeable horsepower gains.... the engine will just run cooler.

 

I went back to the old 195 one. I guess only if you're running the SCT you'd see a difference with a 180

 

guess youve already installed a 195 now but i love my 180 cuz when its 100 in the dog days of summer she peaks at 195 not 215+. just runs alot cooler

 

I put a 195 on mine and she doesn't get anywhere near 200 in this crazy heat.

 

Will run a little cooler, and you will have a slight gain in performance, but not enough to be recognized except by a dyno. You will also have a slight loss of fuel economy.

The cooler temp will cause the PCM to richen the mixture, which depending on your other mods could be a good or a bad thing.

For example, if you have a lot of "breathing" type mods such as CAI and headers you will run a bit lean, combine this with a tuner set to performance and it will advance the timing considerably, also leaning you out. A 180* thermostat would be a perfect, inexpensive mod to bring the A/F ratio back to stock specs.

Do you need a 180* or will it perform better than a 195* in your truck? With a stock or close to stock truck, it probably wouldn't matter much with either one, but once you start modding a bit, it wouldn't be a bad idea to use a wide band to determine which is right for you...

 

Will somebody please put an end to this idea that a lower temp thermostat does much of anything other than keep the truck from warming up quickly in the winter. It's just a switch. If temp=X, then open...

 

As Hammer stated, it can compliment other upgrades, but by itself on a stock truck, its pretty useless.

 

I'm just worried that my truck is now running over 205 degrees with the a/c on. If it doesn't do that much to a stock truck, then why would Hughes recommend it in combination with their plenum fix kit? Is it just to control the pinging?

 

Hughes also sells an epoxy filled manifold. Does that mean everyone should do it?

The PCM expects a 195* thermostat, so, by changing it to a lower temp, without cluing in the PCM, it is possible to actually introduce driveability problems thereby. If you are doing 'other stuff', including a tune, then maybe it will help. But, just going to a lower temp stat, by itself, won't do you any favors.

And yes, with the A/C on, the truck WILL run hotter by a few degrees. The condenser is going to be warming the air before it gets to the radiator, and the compressor is going to put an additional load on the engine. Therefore, more heat.