Thread: 180* T-stat

Thinking about buying the zzp 180* t-stat. How will my PCM react if I install this? Do I need a custom PCM and/or have my PCM tuned to the 180* t-stat? Is the t-stat easy to install? Write-ups or tutorials?



Random question: My car shifts gears at around 2500 or 3000 rpms, is this normal?

Originally Posted by J_Man55

Thinking about buying the zzp 180* t-stat. How will my PCM react if I install this? Do I need a custom PCM and/or have my PCM tuned to the 180* t-stat? Is the t-stat easy to install? Write-ups or tutorials?

Before you go and buy the t-stat, think about why you want to install this. If you don't know why, then do some research and find out the benefits and downsides to the mods.

Personally, I am running a stock 195° stat right now because I am most concerned with fuel mileage. I have found that a 180° stat in a daily driver will cause me lower fuel mileage. I do convert over to a 180° stat when at the track. But for everyday use, I keep a stock stat in it.

yea about the 180 tstat i recently asked people on here what is soo good about it? Plus my GTP is a daily driver and it will lower your MPG and will not gain hardly an HP so its a waste of 10 bucks. take the 10 bucks and put it in your gas tank =]

thanks reptile i believe it was you or senthicsheild that told me put the money in the tank =]

I have noticed a decrease in MPG with a 180 stat. I may switch back soon. Heck I may not even install the 3.4 pulley and stuff I ordered.

Over 100 years of engine research has determined that ~195* is the ideal temperature for combustion. But my GP still runs cold with a 195*. Either that, or my temperature gauge ain't right...

How do you know its running cold? I used to think halfway on the Impala's gauge was 200, but according to my scanner 200 is a notch or so left of the half mark.

Point is, temperature gauges don't scale linearly. My trucks were like that (100 at the bottom, 210 middle, 260 at the highest), but I thought cars were different. Apparently not.

Originally Posted by Zef_66

Before you go and buy the t-stat, think about why you want to install this. If you don't know why, then do some research and find out the benefits and downsides to the mods.

Personally, I am running a stock 195° stat right now because I am most concerned with fuel mileage. I have found that a 180° stat in a daily driver will cause me lower fuel mileage. I do convert over to a 180° stat when at the track. But for everyday use, I keep a stock stat in it.

I am quite curious as to how much actual fuel savings there is with the 195 as compared to the 180 Tstat. Numbers or estimated MPG's would be great

Thanks!

Zef, so your saying that you'll spend hundreds of dollars modding your GTP but won't risk losing a few tenths off your mpg by going down to a 180* tstat? Weird. Also I'm pretty sure that you do have to change your PCM (or just a setting in it) to benefit from your 180* tstat.

On the highway the car will run a little cooler with a 180 on stock pcm. Because the air flow threw the radiator is enough to cool it. But in stop/go the fans will keep it at stock temp.

I'm curious to see if my gauge is right. It seems low. The ls1m should tell me I guess.

I run a 160 and all the mods in sig @75mph I am getting around 27mpg

@ 65 MPH through IL, I got 33 MPG with a 180*.

fwiw, with my fans set to match my 180, my temps stay between 186 and 175.

Originally Posted by N3p

Zef, so your saying that you'll spend hundreds of dollars modding your GTP but won't risk losing a few tenths off your mpg by going down to a 180* tstat? Weird. Also I'm pretty sure that you do have to change your PCM (or just a setting in it) to benefit from your 180* tstat.

What's the point of the 180* tstat though? He's right that engines are most efficient (and thus make the most power) at 195*. So, why have the 180*?

Originally Posted by GeddyLee

I am quite curious as to how much actual fuel savings there is with the 195 as compared to the 180 Tstat. Numbers or estimated MPG's would be great

Thanks!

I know for a fact I lost a 2-3 MPG on my last trip home (about 5.5 hours) due to a 180* tstat. Highway mileage has returned to normal since returning to the stock temperature.

Originally Posted by Sabrewings

What's the point of the 180* tstat though? He's right that engines are most efficient (and thus make the most power) at 195*. So, why have the 180*?

Use whatever works best for your car. Mine likes the 180. and based on what I've read it seems to be the optimal heat range.

http://performanceunlimited.com/cobr...hermostat.html

http://www.roadandtrack.com/article....&page_number=2

Originally Posted by Sabrewings

What's the point of the 180* tstat though? He's right that engines are most efficient (and thus make the most power) at 195*. So, why have the 180*?

Cooler engine normally means better performance & reduced knock.

Originally Posted by N3p

Cooler engine normally means better performance & reduced knock.

Better performance... I question that. Reduced knock... That's what I have a tuner for.

My point is, why sacrifice efficiency in the pursuit of power if you don't have to?

There is nothing wrong with looking for the balance between performance and efficiency.
The Road and Track take (you can find similar non Internet forum articles everywhere).

Engine-management computers rely on the as-designed coolant temperature (typically 193 degrees F) to better atomize fuel, maintain heat-exchanger efficiency, provide lower emissions, optimize fuel economy and other factors, so running the engine colder than designed can have multiple ill effects. These are the sort of effects that are not immediately apparent, so such issues are more long-term durability concerns.

Tuners often fit 180-degree F thermostats to give hot-rodded engines a larger cooling margin for when they’re making tons of heat (horsepower) at full throttle. This is a bona fide need on an engine that has sprouted a supercharger, but simply fitting a cooler thermostat to a stock engine will not lower the intake air temperature enough to matter and will not support a meaningful timing increase.

Cooler than 180-degree thermostats are not recommended on modern cars. Most domestic automakers’ engine-management systems go into open loop at 168 degrees F, meaning the engine is operating in its warm-up mode with perhaps an overly rich mixture and un-optimized ignition timing. Eventually the computer will consider such long warm-up times abnormal and could trip the Check Engine Light.

Furthermore, higher coolant temperatures promote engine efficiency, especially for fuel economy and emissions, and reduce cylinder wear (a cold block wears faster than a warm block), and the engine internal dimensions have been set for the designed operating temperature. If you’re really beating on your car in the summer and figure it’s overheating, then a 180-degree thermostat could be the answer to return your coolant temps to as-designed levels, but anything colder is counterproductive.


another related thought. If you are running an IC or going to, most rely on the radiator puller fan(s) to cool the FMHE. Typical fans settings with a 180* thermostat is 176 -182* whereas the stock fans settings with the 195* is 208 - 212*.