CT checking in here.
This thread feels familiar.

As it'* been said, 15F degrees won't have a huge effect. Why does either side argue over this 15F degrees? The end answer from my viewpoint is I am only trying to help the person with a plastic intake manifold to not break down sooner, and the supercharged person to get the best mileage and power while still passing emission testing w/o any issues.

Afterall, if more heat makes the engine more efficient.... why didn't GM use an even hotter thermostat. There are points at which heat and cold are better for certain things. The engineer that designed this motor made certain choices for reasons that will remain a mystery to us forever. (I like to look at the coolant passages next to the EGR in a plastic composite upper intake manifold).

Have either of you 95LHS or Cooey considered taking a testing approach to this debate?
Log information on your current 195 T stats
Log information after changing to a 180 T stat
And then changing the temperature range hotter with another thermostat and logging information with that.

From the debate and heated discussions and I'll quote a small section
As an engineering student, I can confirm this. The basic theory goes like this:
1.) The hotter the combustion chamber temperature, the less heat loss there is through the block/heads.
2.) The less heat (energy) lost through the block/heads, the more there is to power the car. "

Those of us here have proven through actual trial that lowering the temps has not negatively effected performance, but enhanced it. As students learn...sometimes theory does not remain cosnstant when variables are introduced. An engine being many systems built on each other...there are many variables that do not remain constant.

As engineering students are you willing to risk what is necessary to prove or disprove the theory of a hotter engine producing more power and running better? Since the club testing has been 15F degrees cooler, let'* say you run 15F degrees warmer. However take into account that the fan turn on temps etc in the PCM would need to be adjusted up.

Had I known my question would have started such a flame war, I would have pm'ed someone. I had no idea people would get so "heated up" over thermostats.

LOL..Their T stats must be malfunctioning...

Don't PM anyone. No matter how dumb or stupid or whatever the question may be, guarantee you that someone will be thinking the same thing and are afraid to ask.

Plus, PMing a question prevents others from benefiting from the answers.

People are passionate about their cars. They only want what is best for them however many times best is a relative term. Best in MPG, best in performance, best in reliability, best in longevity etc....

When you ask a basic generic question such as 195 vs 180 T-stats you are going to get a variety of answers all based on what people feel is best to them.

Try asking the question with a little more detail and narrow it down such as.

I have a 00 Bonneville SSEi, I live in Ohio, the car is modded and I want the most power available, which T-stat should I use?

Or

I have a 00 Bonneville SSEi, I live in Ohio, the car is stock, I want the best MPG I can get, which T-stat should I use?

I find it very difficult to get interested in threads that have useless topics like Please help, or T-stats, or Baked Ham. Not only will having detailed thread titles get the right people in to answer your questions but they also make searching easier for others who may have the same questions.

BTW, my car runs a 160 T-stat year round, and its best for me. For you, not so much.

My trans temp runs about what my ECT does,

what are the ramifications of 160 vs. 180....this topic doesn't seem touched on much, and i know it'* quasi off-topic from what'* in this thread thus far, but does anyone have any thoughts on this? is that extra 20 degrees F any better? is it better in only warmer climates? does it reach a point where the engine is running too cold?

Nick, you won't be able to run it without a custom PCM. There'* probably only 4 or 5 cars on this forum that run a 160. I'm one of them, but I have an underdrive water pump pulley as well, and some other modifications.

With a 160, it will take your car MUCH longer to warm up.

The reason behind the custom PCM is that the stock pcm has a low end value it expects the car to reach. I think it'* around 165F .. (probably wrong). Therefore the PCM expected temp needs to be lowered for that colder thermostat.