I have an early (cast iron head) 86 which I am assuming is running a 195 degree thermostat.

I was thinking of switching that out to a 180 degree thermostat, but was wondering if I needed to reprogram the computer for the 180 t stat......

I know that if I went to a 160 that I would need to reprogram....

 

Thermostat sets lowest temperature, and has no effect on high temperatures. It depends upon what you want to accomplish.

If you want to help control how hot the coolant gets when moving slowly or bumper to bumper traffic, you must somehow get the fan(s) to come on earlier. Best way to do this is with a chip, can also use a low temp switch to ground the fan relay such as is available from MAD and other sources, or you can wire in a switch to ground the fan relay on demand.

You don't need a chip with a 160* stat, but you can get a chip that will allow a little more advance that takes advantage of the lower temps, and also turns on the fans sooner.

If your's is the usual goal of lowering temps at non-highway speeds, the fan must be delt with or your high temps are going no where!

[Edit] For example today the temps were just above 90* in NJ. I got stuck in some nasty urban bumper to bumper traffic. Craig Marcho burned a chip for me that starts the main fan around 196* and shuts it off around 185* I have the aux pusher fan with a coolant switch that turns it on around 200* and off around 185*. I have a 180* thermostat. Top temp today was about 200*, but would come right down to 185* once the fans kicked in. On the highway I was going below 180* most of the time, and would hit maybe 185* with a downshift and uphill.

Other think I'm sure you know is if you haven't pulled your radiator out and cleaned it and the space between the coolant radiator and condenser you will never get low temperatures.

I think my 180* thermostat is a little to cool in the winter where I drive most of time in the 160* range. But it's a Robert Shaw high flow, so standard 'stats might not get that low. I'm going to check with Moto-Rad and see if they make a 185* or 190* unit. Moto-Rad is in Canada and makes the thermostats for Hypertec.


[Modified by PeteL, 5:22 PM 6/22/2002]

 

I went with a 180 stat --got a jet fan switch that kicks the fans on at 200 and off at 185. Then wired my fans together (see c4 tech tips ). Works awesome. Highest my car has run since the mod is 204. Lots of traffic here --so I wanted it to run a bit cooler. Didnt see any sense in spending bucks on a chip that no one says even helps the L98's exept to make em run cooler --cost me 45 bucks and less than an hour to do everything.

 

You dont need a reprogram for the 160 thermostat. My chip isnt reprogrammed for it, and all Craig changed was the fan settings. Change to whatever thermostat you want.