I would think it be better to have the pcm tuned to enter closed loop at a lower temp, besides if you lost gas mileage its because it IS running cooler so the fuel/timing maps are different. Also you can use a 160* all year round and just tune the fans to come on at a higher temp for winter.

 

thanks anyway shoe, BTW your webpage is a very helpful site.

thanks,
jeremy

 

That won't change the fact that the thermostat opens at 20° cooler. When it's really cold out, your fans won't even come into play.

 

Now that I'm tuned for the 160 it seems my car stays in the mid area, whatever temp that is. With the a/c on it goes over the mid a little and with it off it stays in the middle or slightly below. I live in a hot climate so Im not sure if that's normal or what. I would feel alot better if it would stay below the half mark. Just to play it safe I want to get a heavy duty electric water pump and a better radiator. That should do wonders here in this AOR.

 

that sounds about right when driving around town. does it stay around the mid line when your on the freeway? id think i would come down. mine is usually around the middle line(210) in town and just below the first line up(185) while driving on the free way. this is in 100 degree bakersfield heat.

jeremy

 

Really? Any links, I am interested.

I duno I think it depends on the car. W/ the 160 my car ran very cold like at 160 all the time , then again I did have the wrong 160 stat, I had a SBC 160 stat. Dumb autzone.

 

during highway driving it drops a little below the half mark but never more. I havent found much of a long stretch of highway to really give it a chance to drop though.

 

i live in cali ive had a 160 thermastat for a year before i did tune to run at 160 id put it in but dont think it did anything before tune.but our engines were designed to run hot compared to older cars.i just passed smog if you dont have a check engine light no problem.

 

lol shoebox so you've never seen a car overheat when its cold out due to the fans not working??

 

I have installed the Hypertech power tune on my 95. I know from a previously owned 95 that the fans would come on in moderate ambient temperatures with the power tune. I went in and raised the fan limits but think I lost the power tune in the modification. The hypertech is a pretty brain dead way of super tuning the car and doesn't allow for much adjustment or visual confirmation of what is actually happening. I bought tunercat but can see the need to learn a few million things before diddling with it.

Anyhow. The stock 180 degree thermostat is a dual spring affair that fits nicely into the housing. I bought what I thought to be a reasonable replacement through carparts.com. When I pulled the stock thermostat is when I realized the huge difference between the two. I'm afraid to use the 160 aftermarket because of its fit and the fact that it doesn't block the lower apperature that keeps coolant from circulating in the bypass (or open loop) mode for quick warm-ups - I would suppose. The lack of a bypass block off isn't too much of a problem for me but the sloppy fit in the housing is definately a concern with the carparts.com unit. Does the hypertech (expensive) thermostat fit better or is it a loose fit too?

thanks

 

DO NOT use the wron thermostat! Spend the $10-$20 for the right one and be done with it. I have run a 160 stat for the last two years, Summer and winter. FWIW, my gas mileage IS NOT affected, my engine DOES NOT take forever to warm up, and I have PLENTY of heat during those Chicago winters. Probably the only "bad" thing a 160 will do is slightly increase your emissions. Other than that I don't really think there are any MEASURABLE downsides to running a 160. I'll take the throttle response and resistance to detonation any day.

As far as temps go, I have an Auto-Meter temp. gauge installed, and it shows ~165 going down the highway, around 170-180 in town, and then on really hot days with the air on in traffic it might touch 195 or 200.

 

Good advice because after posting the message I drove down to summit and bought the hyperstat unit ($17.95). It HAS the lower spring and foot valve and comes bound to the flat rubber o-ring establishing it securely in the center of the housing.

The only reason I switched to the 160 thermostat is because of the powertune. I don't want to mess with it. The car only moved 300 miles this year and if my plans remain, won't see a whole lot more each succeeding year.

From what is on the internet, the reverse cooling of the LT1 sets it apart from other engines because the heads get the coolant from the radiator first. We probably all understand what this means. Relatively cool air from the top of the engine due to cooler running heads. Less detonation because of that and hotter cylinders for the reason of reverse cooling. I've read the hot block is a plus for combustion while the cool heads are ideal for timing and compression. I'm not convinced that cooler is better for the LT1 but I do know I don't want to fiddle with the fan temps.

Thanks...