160 degree thermostat

[kchritton]

I want to replace my 180 degree thermostat with a 160 degree thermostat in my 1996 cavalier 2.2. Any suggestions where I could find one?

[Classicrocjunkie]

There isn't one specific for us. You can take one from a Chevy 350 and trim it down to fit. We've done this before.

[J-Ri]

Many OBDII vehicles have a code for "ECT below regulated temperature"... I forget the number, but I've seen quite a few. Just be prepared that there is a possibility you could get the SES light on if you don't alter the ECT sensor wiring (with resistors) to read about 20* higher than it actually is. If you ever take it to a shop, make sure you tell them that you did that, otherwise you might get billed for an hour of them chasing a ghost.

[manicmechanix]

I would advise against putting a thermostat below 180* in a street car. And as J-ri said if you happen to have a 195* it might be best to stick with stock to not set a code. In engine tests 180 is about the minimum you can go without drastically excellerating cylinder wall wear. Besides if you are running a 160 thermostat in cool weather the oil might not even get hot enough to fully boil off moisture. Usually oil temp runs about 35-40 degrees higher than coolant temperature. A 180 puts you right over 212 boiling point with margin to spare. I doubt you would gain much of any performance advantage with a 160* T-stat anyway.

[denisond3]

Im curious why kchritton wants to do that. If its to prevent overheating - then its likely its time for a new radiator for the car. Radiators are consumables, like gasoline and tires - but slower. I figure once a car has passed ten years, the radiator has paid for itself, and is on borrowed time.
Good Luck anyway.

[J-Ri]

A lot of people think it helps a lot in performance. I would tend to disagree with that, but can't prove it. The car always feels faster if you think what you did make it faster. I went with a 160* in my truck because when I'm offroading it's not uncommon for the engine to be under full load and the vehicle barely moving. In that scenario, a lower temp thermostat gives you just a bit more room to spin the wheels before you get too hot. I'm sure the radiator isn't plugged too because pulling a trailer going 75 with the A/C on it stays right on 160*. Just a matter of the fan not being able to pull enough air for the big V8.

I would have to disagree about the radiator being a consumable. I have the original radiator in my '86 truck and it just started leaking a little bit around the side tanks last year. The coolant (green) should be flushed every two years. Dex-cool they say can go a bit longer, but I say Dex-cool can be immediately replaced with non-silicated green coolant.

[manicmechanix]

Originally Posted by J-Ri

A lot of people think it helps a lot in performance. I would tend to disagree with that, but can't prove it. The car always feels faster if you think what you did make it faster. I went with a 160* in my truck because when I'm offroading it's not uncommon for the engine to be under full load and the vehicle barely moving. In that scenario, a lower temp thermostat gives you just a bit more room to spin the wheels before you get too hot. I'm sure the radiator isn't plugged too because pulling a trailer going 75 with the A/C on it stays right on 160*. Just a matter of the fan not being able to pull enough air for the big V8.

I agree. Now I don't think it's a huge deal with a 160* increasing engine wear or the oil not getting hot enough, especially in certain circumstance like offroading and in the summertime. Of course the engine is only going to run as cold as the radiator,fans and cooling system allow. But I'm guessing your truck has a V8 or V6. Although I think a 180*-195* with bigger radiator/bigger fans/auxillary engine and trans coolers is the best solution it sure isn't the easiest cheapest or simplist. 4cyls have higher engine wear rates already in general. It already has a 180* which is as low as I would go in a 4cyl. And like you pointed out a cavalier is basically only going to be under heavy load at speed, as opposed to a truck. I just don't see much of anything to gain with a 160* in a Cav and more to lose. I'm sure you know all this, I mostly passing info on to those you might not lol.

I would have to disagree about the radiator being a consumable. I have the original radiator in my '86 truck and it just started leaking a little bit around the side tanks last year. The coolant (green) should be flushed every two years. Dex-cool they say can go a bit longer, but I say Dex-cool can be immediately replaced with non-silicated green coolant.[/quote]

I agree Dex-cool can be replace with original green and sometimes it should be. I had changed the Dexcool in my Dad's Impala (less than 4 years old and only 40K miles). It was already starting to show signs of slightly solidifying as Dex-cool seems to like to do. A couple months later the new Dex-cool is looking worse. So flushed out the Dex-cool and put Green in and now it looks real good. This Imapala is the iron-headed 3.8 with the pressure cap on the radiator. A lot like iron-engine trucks with the cap on the rad that Dex-cool reeked havoc with. It's something about not having the pressure cap on the resevoir doesn't keep air out as well and Dex-cool doesn't tolerate air. Green doesn't mind air at all. And yu can switch dex-cool out or even mix with the original green. You got to figure all the extend-life anti-freeze on the market that says it can be mixed with anything is for all intents and purposes Dex-cool too.

[J-Ri]

I've got trans and P/S coolers on the truck, but electricity doesn't like water/mud, so I'm not going to be adding fans to it. I probably will get the biggest radiator that will fit when I replace mine in the next couple months.