Thermostat - how cold can you go?

Re: Thermostat - how cold can you go? (VWhombre)

I pesonally run an 80 degree celcius t-stat. Anything much colder is designed for extreme environments. If you run too cold of a thermostat your fuel mileage will suffer because the car takes longer to warm up, and can drop too much on the highway. Furthermore, much colder of a t-stat and your oil will stay too cold, which won't allow any moisture that has found its way into the system to boil off.

Re: Thermostat - how cold can you go? (VWhombre)

What Patrick said.
In my car, I also have the lower temp. fan thermoswitch (185F/207F -vs- 195F/217F-stock) . You'll need to install the thermoswitch with the lower temp t-stat; otherwise, your car will reach the same ultimate operating temp., but take longer to do it.
Fan thermoswitch controls ultimate max. coolant temp.
Thermostat controls how long it takes to get to max. coolant temp.

Re: Thermostat - how cold can you go? (VWhombre)

Isn't stock 180º? 80ºC is 176ºF. Is it worth the trouble to lower the temp 4ºF?

Re: Thermostat - how cold can you go? (rockin16v)

Actually, a cooler, denser mixture means you can advance the spark more without detonation. The danger lies in dipping into the warm up cycle and taking the O2 sensor out of the loop.

Re: Thermostat - how cold can you go? (VWhombre)

80C

Re: Thermostat - how cold can you go? (VWhombre)

I run mine with cold fan switches, 160F thermostats and Evans coolant and still manage to run 210F to 230F oil temps in hot (95+ temps) weather. I don't think 160F is too cold here in Nashville, TN. Depending on your climate this could certainly vary.