MaverickMLFD371

Another mod into consideration within the next 2 weeks is a Low Temp. Thermostat. I see adverstised that they make a 160* and a 180* thermostat. I have never done a mod like this and in my mind, making the engine cooler means the engine will run stronger. I've been trying to see if I can find a manual for my car but cant seem to find it anywhere and find the location of where the thermostat may be on this car. Hypertech is the one thats been advertising for the thermostats and they are like 20 bucks! Is there a benefit of going with a 160 instead of a 180* thermostat? Are there any flaws with going with the smallest one or are they both good??

Any inputs on thermostats or any experiences with them? :scratch:

mr_speedvision

Go to Advance Auto Parts and ask for a 312160 or 312180 Prestone thermostat(160,180), and a 35489 Fel Pro gasket. Under $15 and no shipping, go ahead and get some antifreeze too. Should hit that $20 mark now, Hypertech just charges more for their name. As long as the outer diameter is the same it doesn't matter what the thermostat is "suppossed" to fit it will work just fine. Take note of how the thermostat is positioned in the water neck. The replacement unit must go in the same way.

281GT

Ford ships the 05 Mustang GT with a 180 degree thermostat from the factory. using a 160 degree thermostat is NOT recoomended because the computer with think the engine is running too cold as though it is only partially warmed up and my run in open loop mode all the time. Not good.
I got this info from a document on Ford's website.
Follow the this link:
http://www.fordvehicles.com/cars/mus...eatures/specs/
Click the Manufacturer's Specs (PDF) link and look under the cooling system section and you will see that the GT comes with a 180 thermostat from the factory.

BlueCar

Does that link say the low speed fan is supposed to come on at 214 degrees and the high speed at 225 degrees? That seems hot to me. :shock:

MaverickMLFD371

Wow, thanks for the tip. Looks like I wont be needing this mod. Now time to start saving for the shifter!

Dysan

Quick question....one thing that I've noticed is when the engine is in "open loop" mode, the throttle response seems much better. What would be bad about running in open loop mode all the time?

ski

It will probably not pass a tailpipe emissions inspection.

281GT

The problem with running in open loop mode all the time is that the engine is running with a predetermined set of fixed parameters and ignoring input from most of the sensors. If you're going to do that you might as well be runing a carburator because the engine's ability to adjust for things like air density, ambient temperature, altitude, ect is gone in open loop mode. Open loop mode is there only for certain circumstances such as when an O2 sensor goes bad or when the engine is cold. Most O2 sensors don't work right below certain temperatures so the engine just runs on fixed settings until it reaches a temperature where the sensors do work properly. If you are finding throttle response is better in open loop mode you may need to adjust your tune to improve it. Also keep in mind that when you just hit the throttle with no load the computer can tell the difference so just tapping the throttle may not be an accurate indication of what is really going on. The only way to know for sure is to test. Make a run with the car in open and closed loop modes and see in which mode it runs faster. Either do this at the strip or use a G-tech meter or similar device. Seat of the pants feel means nothing. Use some sort of accelerometer like I mentioned. It's the only way you will know for sure. Generally I would stay away from a colder thermostat. The only reason for doing this is because it can reduce the intake air temp but the other side effects can cause problems. I would try a cold air kit or other means to get colder, more dense air into your engine.

mr_speedvision

You put a 160* thermostat for several reasons: to reduce engine temperature (in conjunction with colder spark plugs) when using higher compression pistons in order to help eliminate valve clatter(detonation) enabling you to advance ignition timing, cooler engine=cooler oil, 02 sensors signal vary by exhaust temperature not engine temp, cooler under air temp means cooler air charge, O2 sensors will begin to read a LEAN air mixture and the ECM will RICHEN the fuel mixture to compensate, more fuel per square inch=more power. I did not personally program the new ECM for use in the new Mustang but, when the knock sensor senses detonation it retards engine timing to compensate, cooler temperature less timing retard. Most ECM's let the fuel system run in closed loop for a timed interval to reduce emissions. The coolant mixture does not dissipate heat at 100% efficiency: a 160* thermostat will not open until the coolant in the radiator is roughly 160*F. The coolant may be at 160*F but the rest of the engine will be much hotter. The engine temp may only go down 10* not a lot. Now assume that the ambient temperature outside is 70*F, at 50* F do you have any problems with your fuel system running in closed loop mode? 40*F? I live in Louisiana temperatures range from 30*-100*F. I can feel how my car performs differently at different temps. Yes I said feel, I have a g-tech meter but when I can feel a difference it weighs a lot heavier than a miniscule change that my meter says. JMHO.

05sonicbluegt

I agree with the two posts above, running a 160 thermostat with fans is a good idea for those of us in warm weather. Just because its a 160 thermostat doesn't mean the engine is only going to stay at 160. In my vette I would put the 180 back in for winter driving.