I know there are a bunch of smart folks on here. This problem has already been solved by someone.

What is the factory temperature?

What is the ideal replacement temperature? Assuming a blistering climate...

Is there a workaround to keep the fan running, or change it's on/off temperatures?

Get to work!

I see guys selling and installing 160º into these cars. I imagine it's a 180º stock because I can't see dropping it more than 20º but I have NO hard evidence of such!

Drill a few holes in the stock one (1/8" or so). 160 stat is going to kill your fuel economy when it gets cooler out.

Stock is 187. Doesn't make too much sense to go to a 180 for cooling so most go to the 160. To change the fan points to match the thermostat you will have to have the PCM reprogrammed. We are currently working on having reprogrammed PCM's available.

160 stat is going to kill your fuel economy when it gets cooler out.
Most people reinstall warmer thermostats in the winter months anyways, to make their heaters work better. :)

Most people reinstall warmer thermostats in the winter months anyways, to make their heaters work better. :)

Bah! Who needs heat anyway? LOL

Bah! Who needs heat anyway? LOL

When it's -20º outside... I DO!:wink2:

170º would be nice but I'm sure there is no such animal.:slap:

When it's -20º outside... I DO!:wink2:

170º would be nice but I'm sure there is no such animal.:slap:

I'd bet 2-3 1/16" or 1/8" in the stock stat would drop it into that range.

Depends on what you're going for, max HP or max longevity...

About ten years ago a mechanic friend I know bought two GMC trucks at an auction. The story was that the trucks were owned by a company that went bankrupt and both were on the auction block to be bid on together. My buddy (Rick) had planned them to fix up, and re-sell them. Both had approx the same miles on them and both had the pretty much the same mechanic throughout their service lives. Both also had impeccable service records.

I went with him to drive one of them home. Both trucks were tired but they started and ran well. On the way home we noticed that the one he was driving left a trail of smoke when heavy on the gas. Mine didn't burn oil at all. He decided to just rebuild both engines at the same time as both were nearing 200,000 miles. Later he showed me the two blocks after disassembly., One needed a ridge reamer to remove the pistons and needed a massive overbore, the other one had a nice bore still and didn't even need oversized pistons. Puzzled why one was in such bad shape, and the other was pretty good, we checked the records: The only difference we could find was one truck used the stock 190 deg. thermostat for all it's life, the other used a 160 deg. thermostat under a "chrome" thermostat housing. It's Driver likely changed it (along with the chrome), perhaps to gain some horsepower. This went totally against what I suspected would happen. I thought GM simply used a high temp 'stat to keep the EPA happy. Turns out, it's more than that;

Rick explained; an engine needs to heat up it's oil beyond a certain temperature to better burn off impurities in the oil. If the engine stays too cool, it's actually worse than running hotter, even if the engine seems "peppier" after the change...

Theoretically, the hotter an engine runs, the more efficient it is..............until you see smoke, then RUN! :p

I posted a reply to this same question that someone else ask, so I'll keep this one simple and to the point. If you want the full explanation you'll have to do a search.

Back in the good'ol days as in the pre-computer era, you could do this and get away with it. The reason you wanted a colder engine was to keep the fuel vapors thinker in the manifold giving you better performance but crappy gas milage...but who cared back than when gas was 99 cents. (there were other reasons, but this was the Primary)

Lets get to todays auto's....hence the computer era. You can install a 160 or 150 or 100 or whatever you like if it makes you feel happy and you'll sleep better at night. The problem is...the computer will not turn any fans on untill the temp reaches the factory level. So, you just installed a nice $22 160 thermostat....guess what...engine is still going to reach that 220 mark and than the fans will turn on. Reason they want a hot engine is better atomization of fuel and to burn all the fuel off..and a few other stuff

If you want a cooler running engine you will have to install the 160 therastat and re-program the temp sender or replace the temp sender with a unit that will "trick" the computer into thinking the engine has reached the operating temp and kick the fans on to keep the engine cooler, but than again, now you have a different problem...more electrical draw on the alternator which creates drag on the engine....so in essance you are loosing power....

The power gains you will see by swapping out the thermastat is very little if anything.

If you have money to burn like we burn fuel, by all means replace the thermostat. It just won't make a difference.

How many of you seen the advertisement of the little magnet that wraps around your fuel line claiming that if you direct the atoms in one direction you'll get better fuel mileage?
BALONEY right? well picture that with your 160 thermostat....sorry i have to be the bearer of bad news.

Yeah i know long read...enjoy...

I posted a reply to this same question that someone else ask, so I'll keep this one simple and to the point. If you want the full explanation you'll have to do a search.

Back in the good'ol days as in the pre-computer era, you could do this and get away with it. The reason you wanted a colder engine was to keep the fuel vapors thinker in the manifold giving you better performance but crappy gas milage...but who cared back than when gas was 99 cents. (there were other reasons, but this was the Primary)

Lets get to todays auto's....hence the computer era. You can install a 160 or 150 or 100 or whatever you like if it makes you feel happy and you'll sleep better at night. The problem is...the computer will not turn any fans on untill the temp reaches the factory level. So, you just installed a nice $22 160 thermostat....guess what...engine is still going to reach that 220 mark and than the fans will turn on. Reason they want a hot engine is better atomization of fuel and to burn all the fuel off..and a few other stuff

If you want a cooler running engine you will have to install the 160 therastat and re-program the temp sender or replace the temp sender with a unit that will "trick" the computer into thinking the engine has reached the operating temp and kick the fans on to keep the engine cooler, but than again, now you have a different problem...more electrical draw on the alternator which creates drag on the engine....so in essance you are loosing power....

The power gains you will see by swapping out the thermastat is very little if anything.

If you have money to burn like we burn fuel, by all means replace the thermostat. It just won't make a difference.

How many of you seen the advertisement of the little magnet that wraps around your fuel line claiming that if you direct the atoms in one direction you'll get better fuel mileage?
BALONEY right? well picture that with your 160 thermostat....sorry i have to be the bearer of bad news.

Yeah i know long read...enjoy...

Many computerized engines used an old fashion clutch fan. The GMC trucks I wrote about (above) were equipped this way, for example...

In my charger, I went from the factory 198 degree t-stat to a 180, and it made a big difference. It was a 2006 5.7L Hemi. I did not change the fan switch, but it just worked better everywhere. RacerX what do you think about a 1/8" hole in the T-stat? I live in Houston, and it is always HOT.
The car just seems to have more power when cooler. Is there a better way to achieve this?

I wonder what kind of "mules" Intense is using, and what their strategies will be... I am all ears.

Drill a few holes in the stock one (1/8" or so). 160 stat is going to kill your fuel economy when it gets cooler out.

A 160 does reduce MPG. I noticed that after I installed one in my GTO.

The 1/8 inch hole is good. I do recommend that. It equalizes pressure from the low to high an can eliminate any air pockets.

it's kinda like the guy who wants a 3 inch exhaust....is it good...maybe....are there any gains....i doubt it......

If you don't feel like drilling, you can shim the thermostat open. I experimented with a couple different lengths and settled on a .1" in my Z28. This kept the temperatures where I wanted them in summer traffic with a stalled auto. I drove it this way for about 10 years or a 160,000 miles. Having said that I wouldn't change or alter the thermostat unless you plan on paying for a tune.

There are definitely power gains to be had with a lower temp thermostat. But you will sacrifice 2-3 mpg (or more) and perhaps the longevity of your engine.

A stock thermostat should be fine for almost all applications. If the stocker is 187* it should be fully open by +/- 205* That is right where you want to be for optimal efficency. Reprogram your fans to come on sooner to keep the temp below 210* and you will be good to go.