Out1aw

iTrader: (1)

I currently have a 160* thermostat installed on my car from the previous owner. The car is my daily driver, but I am taking a drag-racing only approach to the build up of the car. Does the thermostat decrease gas mileage THAT severely? Also, what kind of power gains will I see out of it? I have a fan-control switch that will be installed in the next few weeks, so would it be smart to install a stock thermostat?

HBHRacing

you really cant look at a thermo as a static HP gain mod. It's really not meant to operate as such. It will change nothing over the stock thermo in general. The only thing that it can do, is help with the possibility of running slightly cooler then stock, when you are able to hold the temps down that low.

What I mean by it is this. The car, the power, the mileage, everything, will be exactly the same if the motor is running 220* weather you have a 195 or a 160 thermo.

If the lowest temp you could hold stock was about 210, and the lowest you can hold now is say 180*, that is where your changes will take place. Figure on the only things being different, is when you happen to be in that range.

When you are in that range, since the motor is running cooler, there will be some slight power gain. With that, since you are moving more air, you will move more fuel and thus lower your mileage in a very slight amount.

The only real benefits of a 160 thermo is that it will take longer to heat up, and it will cool more before the thermo will close. This is going to be helpful year round. It will not effect much in the cooler weather, but it will get you better control in the hotter weather, as well as when your trying to cool down after a run at teh track and such.

Out1aw

iTrader: (1)

So would a fan-control-switch be useless sense I am already running at a fairly low temperature?

HBHRacing

the opposite actually. Without lower fan operation, the lower temp thermo will do literately nothing for you. If your fans run the same, the motor will get just as hot with the 160, it will just take 2-3 mins longer to do so.

When you can use the fans to lower the temp, The 160 will allow the motor to keep colling, to the point that the 160 will shut. This point is lower then the stock thermo, and thus will lower your temp.

Example. stock thermo, fans on high all the time. The motor will cool untill it reaches the temp where the thermo will close, which would be somewhere over the stock rating of 195.

160 thermo, fans on high all the time. The motor will coll untill it reaches the temp where the thermo will close, which will be somewhere over 160.

Out1aw

iTrader: (1)

Thanks for the help. That's exactly the info I needed.

mike m

iTrader: (6)

Hey do you happen to know what wires to to rig the fans to stay on high at all times. My buddies car is stuck on low and we live in vegas soo the 100 + temps here everyday is murder. He has a 160 thermo in it.

HBHRacing

never rig them to be on all the time. It wastes battery voltage, shortens the life of the fans, decreases gas mileage, and isn't necessary.

What do you mean "stuck on low"? The fan runs on low all the time?


If your in a hot climate, take the necessary steps to maintain and boost the cooling system by changing the fluid, bleeding the system, cleaning the radiator entry of debris, installing a low temp thermo and a manual fan switch. If you need/want a switch PM me, I have several.

My25thTransAm

Yeah, I'd also like to know more about how to install a switch to turn that damn fan on. I hear ya Las Vegas, Lubbock is a little bit more tamed than that heat out there.

burnzilla

iTrader: (3)

Buying a 160 does not change your temp.
It simply opens and closes more, but really doesnt help that much.
Your PCM (ODB1) needs to be changed (tuned) so it recognizes the new temp.

HBHRacing

No it does not. The PCM can care less what thermo you have. the only "tuning" that is done, is simple fan temp commands. There is absolutely zero need to tune for a thermo.

burnzilla

iTrader: (3)

I was told by someone who has a 160 that if you do not change the PCM stock temp setting, it wont help much.
Also, a fan switch just allows you to manually control the fan speed. Low/High and Off.
By switching your AC on, the PCM will turn the fans on.
I know, because I do it everyday.

HBHRacing

If you read what I have posted in this thread, it will cover all of this.


you also do not want to use AC to "cool" the motor. While it does turn on the fans (low anytime the comp is running, and high when head pressure reached 248PSI) the heat being pulled off the condenser is running directly through the radiator and heating it even more.

burnzilla

iTrader: (3)

So why does the temp for the motor stay down? Are you saying its better to let my engine get hot before the fans finally kick in, than to turn on the A/C?

I dont turn the A/C up, its on the lowest possible speed, and it doenst matter if the temp **** is all the way on hot or cold, it still tells the PCM to turn the fans on, which cools the motor down. I dont give a **** about the condenser or radiator, as long as my engine is running as cool as it can.

I do know its not as good to have my engine sitting there idling at 210 degrees + for 5 minutes before my fans finally come on, then for it to be under 210.

HBHRacing

What I am saying, is to use the correct means to maintain good temp. Running the AC (I don't care what "speed" you run it}, is not the correct way.

Why does the temp stay down? Because the fans are running. Turn the AC off and let the fans run on high, temp goes down even further because there is no longer a heat source running across the radiator.

burnzilla

iTrader: (3)

Incorrect.

If I dont do anything, the temp will go to almost 240 ( around there, but well over 210 ) before the fans kick on.

My engine will run 210+ for several minutes before the PCM kicks the fans on.
But, by switching my A/C **** on... hell I could turn it to hot and have it run heat... but either way the fans turn on, my engine stays cooler, never ever goes over 190-200, and I use little to no A/C.

I dont care how hot the condenser or radiator gets, thats what they are there for.
I do however, care how hot my engine gets.

HBHRacing

Ok, I realize that you have a failure understanding and I need to hold your hand through this. your just lucky that I am patience enough to do so, when others would simply throw a quarter at you, and tell you to go to the store and buy a clue.



Read what I posted above. It explains about everything that you need to understand about the effects of the thermo. period. Then read this.


Listen. Stock fan temps are 227 and 235. ok? You with me so far? on a stock thermo, stock fan temps, it will hit around 237, 238 ish before the temp will start to fall. Still with me? Fans will shut down when normal temp is again reached.

That was stock scenario, with stock fan control. Now interrupt that sequence with AC operation. Again, low speed fans come on anytime that the comp is running. High speed will turn on when head pressure reaches 248 PSI. In the process of the fans running to maintain head pressure. The air being drawn though teh radiator will inherently lower motor temp. but only to a point.

There is nothing correct about my statement. Yours however is wrong. If you simply trigger the fans on high without the AC, there is a much larger drop in engine temp. This is simple fact, and what I thought was common knowledge. The condenser is a heat exchanger. It's pulling heat from the AC system. pulling it right trough the radiator. this will raise temp. The fact that air is moving across teh radiator at teh same time will lower temp, but again only to a point. A point which is HIGHER then if teh fans were running on their own, without interference from AC.

I hope you finally understand, because this is the last time I will try to explain it to you, and all your doing is confusing people.

burnzilla

iTrader: (3)

You dont got to be a dick about it.
_______

You said by changing the stat to a 160, it virtually changes nothing. It just takes a couple mins longer for it to reach

Correct.

Thats common sense. If your running 220*, obviously you aren't getting anymore power than you would with an aftermarket stat because within a given amount of time, its still going to reach 220* I understand that.

My point is simply this: Read it carefully.
By switchin on A/C ****, the temp WILL NEVER go over 210*.... ever.
In my dash console, I never ever let my temp gauge read over 200-210.
That means my engine NEVER gets hotter than that temp... EVER.
Yes, if you dont do that, the high speed fans will come on at around 235, and the drop in temp will be significant. I understand that.
What I am trying to say, is that a motor that never ever goes over 210*, is better off than a motor that shoots up to 235nce in awhile, regardless of what the stat is.

TI dont care if its pulling heat from the A/C system... obviously my engine is running cooler then if I would just wait for the highspeed fans.
Unless my guage is lying?
And it doenst just do it to a point.
It stays around 190*-200*, never EVERY goes over.
Then when I take off, or I begin to move again, I shut the A/C off.
Realize, I only do this when I have to idle for long periods of time.
I dont like my engine shooting up to 240, then back down to 180, then back up to 240, then back down to 180, when I can just keep it at 190.


TI dont want the engine going over 210*.. plain and simple.
I understand the sequence that is set to take place, but I also understand 240* is alot, and I dont want my engine getting that hot. I dont care what speed the fans are, as long as my engine DOES NOT EXCEED 210*.

jakebdb56

iTrader: (25)

look, the guy is simply saying:
fans on high with a/c off= lowest temp
fans on high with a/c on = not as low
fans off with a/c off = not as hot as fans off with a/c on

how bout we just take the damn stat out lol. It works quite swell in my GEN 1 sbc(i do realize that gen 3 is a different motor) I run a 18"x24"x2" datsun radiator with it and have no stat. Of course it's open air since it's in the dune buggy but im still running tops 190 at idle in the heat and about 205 going down the street. keep in mind the datsun radiator is a POS.

Only problem I could see with not running a stat is it would put an additional amount of strain on the motor, but not much more than a 160* going on and off in the summer, same thing with a 210 goin on and off. having no stat would get you the absolute lowest temperature (with fans on of course ) IMO

HBHRacing

you don't want to remove the thermo altogether. You will actually overheat. Not only does the thermo contain teh only seal for the housing, but it correctly routes the coolant to the motor. it's actually very important that it remains intact.

Then you have the obvious issues of taking far too long to reach operating temps, which will make you run rich, use gas, etc etc etc.