I installed a fan switch and 160 stat a few weeks ago and I'm still kicking myself for not doing this earlier. First off I don't think my stock stat was opening completely after doing this swap and watching the temps. I installed the 200 - 185 fan switch and I don't think the fan has come on yet with the 160 stat. Although one in traffic, after about an hour it looked like the temp gauge went over 200 but I didn't seem to hear the fan come on and I didn't notice the temp. drop. I don't know if it actually got hot enough for the switch to turn the fan on or if the fan wasn't working, is there any way I can test the fan without having the car heat up (because it takes forever now )?

Anyways, the point is, these mods are cheap and easy and make a huge difference. I know everyone says you need your prom changed for a 160 stat but I haven't noticed any difference in how the car runs, so if there are differnces they're pretty unnoticeable.

 

i always heard that running that low of a stat will cause an open system and wont alow the engine to get up to operating temperature. I plan on a 170/180 and a fan switch this summer.

 

If you have an automatic the lockup torque converter won't lock up until you get to at least 170.

 

You can ground the wire from the fan switch to any good chassis ground and with the key on-engine off the fan should run. If it does and you don't think it's turning on with temp make sure the fan switch shell is at chassis ground. Too much teflon tape can insulate the threads causing the sensor to be isolated from the block ground. As far as the stat, check the pipes after a few K miles. They will be noticeably blacker. My 89 5.7 lost 3-5 mpg when I experimented with a 160. Also a 160 won't generate much if any heat in colder weather. I did fairly controlled mileage tests and with anything lower than the 195 lost some economy. 180 is a decent choice since average temp in stop and go will be close to 200 anyway. This subject is like which oil is better, there are lot's of differing opinions. Fact is a more stable operating temp is better overall for engine performance. Even with a 160 if you sit in traffic it will still climb. The large swing in temp using a 160 is not desireable for driveability. Colder is not always better, despite what you read.

 

No, a 180/185 deg one would have been a better choice for your application....

 

Yeah, I agree with Danno and DJP. I run a 160 stat currently and in traffic with A/C on full blast my temps rise to about 200. Once I get moving for a few minutes it starts to drop. On the highway, the temp stays at about 170. I am going to put in a 170 or 180 soon because it doesn't do me much good to have such a low temp stat around here. Florida is pretty warm all year long and the majority of my driving is stop and go around town.

BTW all my temps are logged with an Autometer Pro comp mech. water temp guage.

 

I didn't want to go with a 180 stat because the fan switch doesn't turn off until 185 and I didn't know how precise all these parts actually are. I didn't want a 180 stat to actually need 185 to open and the fan switch to actually need 180 to turn off which would result in the fan constantly staying on once it starts, or the fan causing the stat to close while I'm driving. And I wasn't sure where to order the 170 stat that supposedly exists because they never heard of it at the Car Quest I went to. So that's why I chose the 160, if I could find the 170 somewhere I'd like to go with that.

 

I am sure you could locate one somewhere else if you look around, but Tuned Port Induction Specialites sells a 170* stat. Check out www.tpis.com they sell for about $10.

 

170 stat is AC-Delco # 10220957. About $6 or so at a dealer. It is typically not an inventory item, but almost any dealer can have it the next day.

 

Yeah, I called the dealer near me and asked them about the 170 stat and the guy acted like I was asking for the cure to cancer

 

"Fact is a more stable operating temp is better overall for engine performance. Even with a 160 if you sit in traffic it will still climb. "
I totally agree. stat temp is the min. temp and fan kick-in temp is the max. 160/200 is a lot of gap.

 

i've had a 160 stat on my car for a while now with a manual fan switch and have had no problems. since the weather is mostly hot down here the car will run higher than 160 anyways. and it only takes a few minutes in the mornings for it to go into closed loop.

 

Try www.gmpartsdirect.com. Just give the dealer the part number, 170 is not a standard temp for any GM vehicle over the last 15 yrs or so. He probably does not know it even exists.

 

Great, thanks a lot. I'll probably through one of those in sometime soon.

 

hmmm, i just bought a 180* thermostat from autozone... :shrug:

 

hmmm, i just bought a 180* thermostat from autozone... :shrug:

 

wats the pn for it price and can u get it a pepboys or kragens and who makes it

 

I run a 160* stat in my L98 and I'm not sure it ever goes into closed loop,always runs real rich.....It never runs over 200*even in the summer sitting in the drive through at the bank....

 

I just installed a 180 stat just to see if there was a noticeable difference. I know for sure now that it's running in closed loop the whole time. But now with my 200 - 185 fan switch the fan is pretty much constantly on. I guess that's not really a bad thing since all the newer cars (in general) have their fans running much of the time. So I'll continue to run the 180 through the summer and see how that goes.

 

ive always ran 160's in my engines. it seems to work fine.

 

I too installed a 160* stat a few years ago and am very happy I did it. My engine runs much better at 160 than at 190+. And my convertor locks up just fine.

 

i hate csk they only sell 190 ones but thats ok but whats really pissing me off is that im running 240 in traffic my ****ing fan is not going on againa nd i just replaced the relay and the fuse is ok so i dont get what the hell is wrong

 

Check the wiring, switch, and motor...

 

Turning on the air conditioning should force the fan to come on.

If you fan is bad, buy one from the dealership. I bought a lifetime guarteed one from Western Auto for $40. After replacing it every other week, I decided to pay $90 for one from the dealership. The one from the dealership only lasted a year though. I replaced the fan w/ a used one and its lasted over 9 years.

If you still have the original one, pay attention to how much it weighs. The western auto ones weighed less and I figured they were just cheaper.

 

160 is WAY too low for a TPI and a 180 is still low. Come on people, they came with a 195, therefore that's what they were designed to run, just stick with a 195! Your fuel mileage will drop with anything lower. You shouldn't always blame your cooling problems on your thermostat. In my case, when I first got my car, I had some cooling problems. First I replaced the cap, checked the fans, then I replaced my original stat, with a new 195 one. I was still overheating. Turned out, I needed a whole new radiator! Now she runs cool! -89IRO

 

I havent noticed it on mine. too much heat is never good. if i can extend the engine's life a little bit by preventing too much heat, even if it means higher gas mileage or sweating cuz of no A/C, then i'm gonna do it.

yea i know im weird.

 

Well, see you're probably not hurting your engine by running a lower stat, but there is no point to it. Your engine (I am assuming it is fuel injected) was intended to run more on the hot side. Fuel injection needs the extra heat to operate efficiently. Now for carbed engines, they like it cooler. Whatever floats your boat!

 

I've read that modern engines are designed to run hotter to help reduce emissions.

 

Yes that, and to make them more fuel efficient. Fuel injection always needs more heat. These engines were DESIGNED to run hot. -89IRO

 

Glad to see someone see's the light. Actually to add one more thing, almost every gas engine from almost every manufacturer for I don't know how many years now run's thier engines at 195. Some Chevy engines like the Cavalier 4 cyl have stock 180 stats but it's not very common anymore. EFI is very sensitive to operating temp and despite what you read the ECM will not compensate properly. I did do detailed mileage tests with 160 to 195 stats. Everything but the 195 resulted in lower fuel mileage with the 160 being the worst. Plus that very wide swing between high speed and stop and go where the temp is all over the place can't be good. With the 160 my pipes got sooty and it always ran on the rich side. Who knows, but it's fun to experiment and learn.

 

I see your points but the light I was seeing was red because after a minute or so of Long Island traffic in the summer my temps were running anywhere from 220 to 240. While FI may like a little more temp then carbs you can't tell me these 220+ temps are good for the motor, and you're talking about a wide range of temps, well this is 195 to 240, that's a pretty big range. The main reason I installed a lower stat was because I installed a fan switch and I chose the hotter of the two switches (200 on, 185 off) and I obviously couldn't install a switch that came on 5 degrees after my stat opened, there's no reason to have the fan on while on the highway, the car will keep itself cool then. That being said I ditched the 160 stat and went with a 180 and the car doesn't run as rich as it did with the 160. And now my fan is on basically anytime I'm not on the highway but the car stays cool but seems to be in closed loop (doesn't seem as rich as before). The car now runs in a much more consistent temp. range then stock and I don't have to worry about my fan coming 15 degrees before the red on my temp. gauge, so it'd be real hard to convince my that my current setup is inferior to stock even though it's running a little cooler and FI likes a little more heat.

I'm not trying to flame at all, just expressing my opinion and experience. I'm just tired of being in traffic and seeing my temp. gauge sit over 220 the whole time.

 

To check your fan you can run the a/c which is an override for the fan. You can also check the fan motor by connecting power to it directly. Also if there is a problem with the fan you will want to check the fuse link and the fuse under the dash. There is also a relay that connects to the fan from the fan switch. The last option I know of is to disconnect the fan from the a/c hard line.

 

I see your points but the light I was seeing was red because after a minute or so of Long Island traffic in the summer my temps were running anywhere from 220 to 240. While FI may like a little more temp then carbs you can't tell me these 220+ temps are good for the motor, and you're talking about a wide range of temps, well this is 195 to 240, that's a pretty big range. The main reason I installed a lower stat was because I installed a fan switch and I chose the hotter of the two switches (200 on, 185 off) and I obviously couldn't install a switch that came on 5 degrees after my stat opened, there's no reason to have the fan on while on the highway, the car will keep itself cool then. That being said I ditched the 160 stat and went with a 180 and the car doesn't run as rich as it did with the 160. And now my fan is on basically anytime I'm not on the highway but the car stays cool but seems to be in closed loop (doesn't seem as rich as before). The car now runs in a much more consistent temp. range then stock and I don't have to worry about my fan coming 15 degrees before the red on my temp. gauge, so it'd be real hard to convince my that my current setup is inferior to stock even though it's running a little cooler and FI likes a little more heat.



I had the same problem but it turned out to be my original radiator. It wasn't flowing any water and holding no pressure. So maybe you've got another problem on your hands if you were getting up near the red part of the guage with the 195. Right now, sitting in hot traffic, it will get just a little over 220 then the fan kicks in and brings it down. -89IRO

 

Well the stock fan doesn't turn on until 240 or 245 and the red on the temp guage is 260, that's what I meant by getting near the red on the temp. guage. I'm sure my radiator isn't as efficient now as it has been in the past but show me any thirdgen that's stock and won't hit 220 in traffic. 220 is a little too hot for me, I don't want to rely on my motor oil to not break down at those temps over extended periods of time.

 

It might be time to replace the radiator. Mine was pretty well plugged up because the previous owner thought the green antifreeze was good for 175,000 miles. It had the original hoses on it yet too !!

I'm running:
New Napa hoses (about $30 for everything)
Modine OE aluminum replacement radiator
Zerex antifreeze at a 50/50 mix with distilled h2o
a 180 victor stat I bought a K-mart for $1 on the clearance rack
New 16lb cap for $1 found on the same rack.

It will get to about 210 at most in traffic when it's hot, but it will stay there. A flick of the A/C switch brings it back down to 180 in about 5 minutes.

 

I'm using a 160 stat, but with manual fan switches. My car never see's over 190. In fact, when I have turned my fans off around 200 degree's and gave her gas...ahahah

My engine likes nothing to do with running warm. The cooler she is, the harder she pulls.

 

I have a 160 stat and should change up to the 180. My car runs at about 190 degrees most of the time anyway so I think the 180 will work better for me. Anyways, I have been reading everything that everyone has added and can only conclude that like everything else with cars, everyone will need different equipment. In my case, fuel mileage is not a primary concern because it is low due to my engine and the way I drive. For me, the lower t-stat and lower engine operating temps are better. When my car was stock, I had only replaced the leaking radiator and replaced the stat with a stock type. My car always ran about 220 and got fine mileage. I find that engine operating temps are one of the most stongly argued areas of engine operation that these boards sees. Keep up the posting though, I like to read every opinion on the subject...

 

not just that, everyone lives in different parts of the nation as well. Like me, I live in Oklahoma and my temp can get up to 235 really quick, even with the fan on. When I was in Michigan it wouldnt get above 190 or so.