Originally posted by 410Fortune
Aldive: You've got it 1/2 right. The computer wants to see a minimum coolant tempature of 190 degrees to switch from closed loop to open loop operation. A 180 thermostat will not keep your coolant from reaching 190 degree's (at least not with a stock cooling system).
My truck (as stated before) has a OVERKILL cooling system, meaning I have the heaviest duty cooling system that was available with a OHV 4.0L, like if you bought a 96 Explorer with an automatic, towing package, and A/C, then added the largest tranny cooler you could find.
Now I have a 180 stat installed and my truck runs at a minimum tempature of 190 degree's (once it;s warmend up) It will get as hot as 215 degree's when towing a fully loaded boat up the rockies (about 4500# total), but thats it. With a 195 stat it will run at 205 degrees minimum and it gets up to almost 230 when towing the same fully loaded boat through the rockies. 230 degrees is not overheating (Almost), but it's too hot if you ask me....
Bottom line. The people who know and want as much Horse power as possible, dont want detonation to occur, and run their trucks HARD will be using 180 thermostats. It may cost me 1MPG in fuel mileage, but I make up for that (big time) with my other mods.....
So a 195 stat will not hurt your truck, but if you want to run a chip, tow a heavy trialer, climb big hills, do some serious 4x4ing in the 125 degree desert, or basically run your truck hard, you should consider a 180 stat.
You dont have to take my word for it, do some research. Go talk to Pat Kunz, or Sven Pruett. These guys know all there is to know about the Cologne 60 degree V6 family of engines. Go ask somebody at Ford Motor Sports, go ask on the EPEC boards, go ask the guys at the EEC tuner boards, go ask the chip makers, go ask the guys at Saleen, go ask the guys at your local 4x4 shops, go ask the guys at your local Mustang shops, go ask the guys at the drag strip, go look at the Ranger forums, then tell me that a 180 stat will hurt your engine...or heck go tell my engine!