160*s of BULL****...

[Brett Garret]

Ok, I finally got the time to go to City Garage and get my 160 thermo put in. Well, I walk in and talk to the guy. When I told him what I wanted he looked at me like a stoned monkey and replyed, "no you will be doing the wrong thing."
I was like ummm how's that. He said it would 1.)make me fail emitions because my car would be 'thinking' its too cold and dump a TON of gas and therefore make me run bad, 2.)i would make my car 'revert' to a primitive state. That long ago they thought makeing a car run cooler would be better but they were wrong and I would receive no benefit of a longer lasting engine or cooler temps. Now, I think this is well... [img]graemlins/bs.gif[/img] BUT Im not a garage mechanic either. The only thing I can think of is there sure are alot of other peeps with lower t-stats in their ride. Which means NOONE will pass inspection and our cars are primitive apes. Anyones opinions? :D

[ June 13, 2002: Message edited by: Brett Garret ]</p>

[Arctc Wolf]

you don't need one until later in the mods process when you have detonation due to forced induction. for now, get a 180 put in. bolt-on mods don't make a lot of heat, unless you start advancing timing a lot like w/ a HPP3, jet chip, ect. the reason you wouldn't pass emissions is that the rings need to be warmed up to a certain temp. to seal entirely. blow-by causes HC levels to go up a lot, causing you to fail emissions. Get a 180 to lower temps a bit and contol detonation w/ basic bolt-on's. later, if you bore/stroke your engine or add a sc/turbo, then get a 160 to control detonation.

[pgriffith]

I did emissions today. I have had a Hypertech 160* stat for about 2 months or more. Car passed with flying colors. Car runs alot cooler. I like it very much and would highly reccomend it. I did not set off any SES light by doing this. I did notice, a little more throttle response. Car runs awsome with this stat. I say do it. If you dont like it its only like $10 to switch back. NO big deal. Do it, its a very good mod.

[navyblue2000]

here's the thing about thermo's.
yes, they will increase emissions, yes they will decrease gas mileage. however, the main reason ofa thermostat is to not so much keep the car cooler for that extra HP that kinda wears out the car sooner, makes it work harder, but helps it cool down faster after you turn it off. this helps the efficiency of the coolant system, and is very good at the track to keep the car cool. However the lower thermo is nearly useless without the manual fan switch, so i'd do that too if i was you, because i run a 180* and i still get to the 210 mark after long driving during summer days. also...rework your coolant mixture so you're running at least 66 water 34 coolant. In my case I'm running 75/25 but that's just preference. water wetter will help as well.

just my 2.02

[FirebirdGT]

From the Technical Database, Engine section:


Thermostat
The 3800 comes stock with a 195 degree (96-97) and a 180 degree (98+) thermostat. A common mod is to replace the thermostat with a 160 degree to increase fuel enrichment, the real facts are:

A 160 just lowers the initial opening temperature, you still can run at 200 degrees or more, thereby creating wide temperature variations to and in the block and heads. You want your engine as HOT as you can get it without pre-ignition (which triggers the Knock (timing) Retard). Efficiency of the engine goes up the more heat the cylinder heads retain - up to the point of pre-ignition, all other things being equal. So you want it just cool enough so that the PCM does not retard the timing. A cool engine draws heat out of the combustion process - less vapor (combustion) pressure, less ability to do work (push the piston down). Not to mention the possibility of oil contamination from unburned fuel (due to lower temps). Pre-ignition can be reduced also by using higher octane gasoline. Reducing the temperature also impacts the ECT sensor, as discussed above in "PCM Operation." The reported ECT set temperature is 170 degrees, thereby forcing the PCM into Closed Loop Condition by "timing out." At which point the the desired goal of increasing the fuel enrichment goes away anyway, as the HO2 sensors will control the enrichment to maintain 14.7:1.

[OneQuickV6]

Also as a side note, if you are adding a 75/25 or similar mixture of water to coolant, PLEASE USE DISSTILLED WATER! Regular water has other things in it like chlorine, and other minerals. I have seen many radiators and cooling systems with rust galore, and chlorine stains from this. Distilled water is pure. Just food for thought, and only costs a buck or two to fill it.

[navyblue2000]

Robert-
the technical database IS WRONG. they all got 195* thermo's. my 2000 had a 195*, or at least it said 195* on it...

[NBMA4V6]

<blockquote>quote:</font><hr>Originally posted by navyblue2000:
Robert-
the technical database IS WRONG. they all got 195* thermo's. my 2000 had a 195*, or at least it said 195* on it...<hr></blockquote>

same here..

no problems here with the 160*

[RedbirdV6]

<blockquote>quote:</font><hr>Originally posted by navyblue2000:
Robert-
the technical database IS WRONG. they all got 195* thermo's. my 2000 had a 195*, or at least it said 195* on it...<hr></blockquote>

Yep they all have 195's [img]graemlins/thumbsup.gif[/img]

[Brett Garret]

The problem i hear is that a 160* thermo wont let the car come out of warmup mode. Therefore jacking your whole system up and it not running efficiently. See from my understanding when it cant come out of warmup mode it is unable to totally complete combustion within the cylinders, (ie.- totally burn off all fuel and air and produce maximum power from given substance). So you keep your system cooler, giving longer engine life, and possibly keeping the cylinders more compact (heat exands, cold contracts). Yet you dont run completely. *Starts sobbing like a little ***** with a skinned knee.* Can someone shead light on this.

[stagen]

Just put it in it's fine. I have had mine for 3 years now with no problems. Sure helps at the track to, especially in Texas.

If your in Houston anytime stop by, I'll put it in for you. Well don't stop by over the next 3 weeks or so. I'm no where near Texas, much less the US. :)

[Guardsman]

Two things: First, Firebird is partly right about keeping everything hotter. Brett, I think what Firebird GT was getting at was that heat will move to the cooler area, so if you keep the heads and block hotter, you lose less heat, however, you still consume heat to keep the block and heads hot, so it's probably a moot point. Anyways, one thing that running hotter does is to keep the area around the injectors hotter, so that the gas will atomize better, thus making more horsepower.
Second, as to the aspect with the computer, running the lower temp thermostat can make the PCM think that the engine is always cold, and will keep the mixture rich. That's where you get the extra HP. The lower mpg is partly because your running rich, but also partly because your mixture isn't being metered by the O2 sensors.

[Dominic]

<blockquote>quote:</font><hr>Originally posted by Guardsman:
Two things: First, Firebird is partly right about keeping everything hotter. Brett, I think what Firebird GT was getting at was that heat will move to the cooler area, so if you keep the heads and block hotter, you lose less heat, however, you still consume heat to keep the block and heads hot, so it's probably a moot point. Anyways, one thing that running hotter does is to keep the area around the injectors hotter, so that the gas will atomize better, thus making more horsepower.
Second, as to the aspect with the computer, running the lower temp thermostat can make the PCM think that the engine is always cold, and will keep the mixture rich. That's where you get the extra HP. The lower mpg is partly because your running rich, but also partly because your mixture isn't being metered by the O2 sensors.<hr></blockquote>

Lower mpg? You didn't read my post... :rolleyes:

[Magnus]

My car is a primitave ape with a 160 thermo.. I passed emissions last fall even with a 3" CatCo cat.

My car also runs pretty decently at the track as well.

[V6Bob]

"...while crossing the desert in my 2002 Camaro, when the 160 stat was in, doing 85mph, I got nearly 36mpg.

On nearly the same terrain the next day with my *new* 195degree pos thermostat, I dropped to 27mpg doing the same speed in the same air on a different day on the same grade pavement (FLAT)."

Jeez, for someone who uses "BS" and "myth" so much...

1. At an 85mph cruise both thermostats are wide open. There is absolutely no difference between them.

2. To think that a thermostat would change mpg from 36 to 27 goes way beyond myth. It might make a 1 mpg difference, maybe (but I don't think so).

The most important thing about a 160 thermostat is that, if the day is cool, the engine is not fully warm, and/or the radiator/fans are set to give more cooling; the fuel injection will be fooled into running a bit richer. The next most important thing is that the temperature of the incoming mixture will be reduced a bit so it will be denser. Differences in "engine efficiency" will be small compared to these.

The most important drawback is that your oil may not heat up as much and may retain more contamination.

This is a mod that is not worth it on anything less than an all out drag car, IMHO. In a street car mostly what changes is the speed the car warms up and the differences are more in peoples heads.