scyzoryk

I have power programmer III. It has an option that can change your computer so radiator fans will turn on at 160 degrees. Do I also need to buy 160 degrees thermostat? or just program my computer?

shoebox

It will let you turn them on that low? If you do, they will hardly ever turn off, even with a 160º thermostat and surely would never go off with a 180º. That is a bit of overkill, not necessary and will waste your fan motors. About 190º is my opinion on when the fans should come on. The old HPP programming that I have seen turns them on at 192º and off at 185º.

Trans AM 22502

a 160* thermostat causes you to lose gas mileage and disables your heater. You can say so and so dynoed a 6HP increase but its bull, the laws of physics don't lie.

Fuel is burned more efficently during higher engine temps, by lowering the operating temp, you're affecting gas mileage in a negative way.


As far as the heater is concerned, it keeps the water entering the heater core from getting hot enough to make it a comfortable ride.

I just got through discussing this with my auto tech teacher last week.

For carbed cars, good, for fuel-injected/CPU ized cars, bad.


Anyways, I would program the fans to turn on @160, its easier and cheaper. (since you already have the HPP, which sucks btw)

drop top steve

The HPP programing turns the fans on at 182/188. My cars runs at 178-180 with the 160 stat and 182/188 fan setting (lt1edit). It does cause a minor loss of economy and my heater well drive you out of the car even in sub freezeing weather.

AW/whiteZ-28

So I should't install this hypertech 160 degree T-stat?

drop top steve

I wouldn't on a stock engine, but would on a heads/cam engine.

shoebox

There is something wrong with your logic. You say the lower temp is bad and then you recommend the fans be turned on at 160º? They will never go off, like I said above. Complete waste and unnecessary.

AW/whiteZ-28:
Put the 160 thermo in when the weather gets warmer.

Hawk

dah, i've had it in for 2 years. It's been freezing here, like 20 degrees, and my heater works fine. Heater doesn't work my ***, i have it in and it works great, how damn hot u want the heater, 180 degrees is fine for water temp. Put it in now, it's worth it. Less mileage maybe, but lower temps is better for the engine overall. Besides, the basic is that lower temps is better for fighting off detonation, thats why u can run more spark advance, or in my case run nitrous more effectively. Later.

TriPinTaZ

i had a 160 stat and HPP3 on my old stock LT1, heater worked fine and car ran cooler. I live in south FLorida and car reaches about 180-190while sitting in traffic for a long time with the 160 stat, it used to get up to 230 or higher with the stock stat. But I couldnt feel the dyno proven 6HP it gives. Fuel economy does decrease a little.
Its worth it IMO.

Trans AM 22502

The temperature described by the thermostat (180*) does not determine the temperature of the engine. How can 180* thermostat be responsible for exhaust gas temperatures in excess of 2000* F?

And, not only did my teacher say it messes the heater up, but it happened to my car. I had a PERSONAL experience with the problem, MONTHS PRIOR to even meeting my teacher. Think about it like this: You are lowering the boiling point of the water entering the heater core by using a lower temp t-stat as well.

The engineers design MOST engines to run at 200+ degrees ANYWAY, thats standard operating temperature. That's where the PCM uses a set A/F ratio to get the BEST gas mileage possible while pleasing the enviro whackos at the same time. By lowering the temperature, you're also affecting the effectiveness of your A/F ratio mixtures. ANd an engine that runs TOO cold can be a bad thing.


As far as detonation )knock) is concerned, thats why the LT1 is reverse flow cooled to begin with, to reduce detonation and to consequently run a higer compression ration on the engine. So a colder engine is really over kill.

I thought to myself when I bought my 160* hypertech t-stat: WHy would anyone buy the 180* version. I found out when it contributed to overheating problems and no heater working.

ANother problem with a 160* t-stat is the fact that it opens 20* earlier, not allowing the coolant to stay in the radiator long enough to cool the block (at least as efficiently as 180* engine)

Which shoebox, explains my backwards sounding logic. If the coolant does not stay in the radiator long enough to get cool (commonly associated with a 160* t-stat) then the engine runs hotter than a 180* t-stat. Whereas with fans, running the motor down is true, but it will lower the coolant temps in the radiator rather than raising the temps in the block.

Why don't you just get a fan switch that you can turn on and off at stop and go/highway traffic.

LT1der

"That's where the PCM uses a set A/F ratio to get the BEST gas mileage possible ... By lowering the temperature, you're also affecting the effectiveness of your A/F ratio mixtures. And an engine that runs TOO cold can be a bad thing."

Trans Am 22502,

I agree with almost everything you say. Shoebox and I had a similar online discussion a couple weeks ago. If you have a stock engine, putting in a 160* thermostat is a waste of time. It will decrease the efficiency of your heater and it will cause your engine to run richer due to a lower A/F ratio, resulting in higher emissions, lower mileage, and sluggish performance off the line.
The cars that should be running 160* thermostats are ones with nitrous, boost, strokers, or higher compression engines. A stock, normally aspirated engine should probably keep the 180* thermostat.

I disagree with you on the fans-- having them come on at 190-200 and go off at 175-180 is an ideal set-up. The stock PCM turns them on at much higher temps (around 220, or when the A/C is on, I believe). Reprogramming the fans for a to come on around 190-200 will help keep your engine cooler in summer traffic and help your engine.

I'm also speaking from experience-- I drove from Abilene to Louisville last month and never saw temps above 160 using the lower thermostat. I got lousy mileage, had sooty carbon from the exhaust all over my quarter panel, and froze mty a*s off when the outside temps got into the 20's. I went to a 180*thermostat the next day and kept my 200* fan switch. Much better!

Bottom line-- don't waste your $$$ on a 160* thermostat unless you are running N2O, boost, or compression. They need the lower temps to stay out of detonation, Stockers run better, leaner and cleaner with a slightly leaner A/F ratio. But getting the fans to turn on around 200 is a good thing.

Dave

shoebox

It helps control the coolant temp which in turn allows dissipation of combustion heat. Lower temps have been proven to enable more agressive spark like Hawk is using. He is using it for good reason.

Obviously, if the coolant is at a lower temp, it will feel less warm when transferred to the air by the heater core (though not everyone's idea of warm is the same and some people don't seem to notice a difference).
I gotta see how a thermostat can lower the boiling point of water . Don't think you will find that in a school book.

The real reason to do the 160 thermostat is to change the programming so more spark advance and other changes can be made. Stock programming is altered to conform to the needs of the user and to provide whatever results desired. Fuel mileage not always being on the top of the list (though it could be).
Too cool can be a bad thing, yes.

Not overkill when changes in the spark curve can cause spark knock and even more important because it is high compression like you state.

If you had overheating problems, then you did something wrong. Probably air left in the system or had a bad thermostat. It has happened to a few people.

A wrong assumption is causing you to waste any logic, here. There is absolutely no difference in how long the coolant stays in the radiator with a 160 or 180. Once either thermostat is open, the flow is the same. They have the same physical characteristics. If you removed the thermostat, then there would be something to talk about.

Use the thermostat for the right reasons and it will be worth it.

...

Trans AM 22502

shoebox

As I said before, something was wrong, plain and simple.

The people here are running computer controlled ignitions. They are trying to push the limits of performance. Proof it is a cheap fix? Again, your logic eludes me.

Yeah, I guess your POV results from a bad experience that few people have had and probably puts you in the 1% minority. Call it a cheap fix if you want, but the theory has been used in the auto performance market for many years, including back when computers were not even used. You can credit Hypertech for making it a popular cheap fix in recent years.

remaxracer45

Awesome conversation, you guys are pretty sharp and make alot of sense. Question is how to magazines like GM high tech get 12-14 horse off a Hypertech and a 160 degree stat? I ask as my programer and stat are on the way. I have a 52 mm throttle body with foil, tb bypass, a KanN cold air kit, iat relocation kit, SLP loud mouth and a trans go shift kit. Is this a waste of $.
I did have a JET stage two which made a ton of difference?
Thanks