What is the correct thermostat for winter driving?

[canada karl]

....for faster warm up and heat?

[Falkenberg]

A proper thermostat should keep the flow through the radiator closed until the engine reaches operating temperature - so I don't think that a higher temperature thermostat will cause the engine to heat up quicker.
You might try to partially block the radiator so that less cold air will flow through the engine bay, I tried that once and I think it resulted in a quicker warming up.

For my standards, heating is plenty also with the stock thermostat. Even my wife didn't complain.

If you experience problems, maybe there is something wrong with your thermostat?

[canada karl]

I thought there were three thermostats with different temps .ie 71...75...80....there must be one for summer and one for winter but I can never remember which is for what?

[canada karl]

I thought there were three thermostats with different temps .ie 71...75...80....there must be one for summer and one for winter but I can never remember which is for what?

[GripGreg]

Karl; I think the 80 degree one opens only when the water temp. reaches 80, meaning, I think, you can get heat a little sooner.

[canada karl]

so the 71 Celsious is for hot summer driving???

[canada karl]

so the 71 Celsious is for hot summer driving???

[Mike W.]

80C, summer or winter. Stats can age and weaken, so if it says 80C, but you have a lousy heater and it never gets out of the blue on the gauge think stat.

In hot weather, if it's running hot, it's over 80C and where ever it's wide open anyway, so a lower stat won't do any good if it's overheating. Well, it might give you a couple more miles before it gets hot, but it's like trying to use a band aid when you need a dozen stitches.

I've driven many miles thru the desert, in 110+ weather, with the A/C cranking with 80C stats. No issue if the cooling system is in good condition.

[Falkenberg]

I have an 80 degree thermostat, temperature can be 40 degrees Celsius in the summer in town traffic, and -15 in the winter, but I see no need for changing.
And indeed, a 71 degree thermostat will not increase the cooling capacity of the system.

[canada karl]

So what is the actual purpose of a 71degree thermostat? Manufactured to accomplish what?

[Falkenberg]

Good question.
I know from the 2002 scene that some used them for racing purposes.

[canada karl]

Actually I was thinking of different thermostats strictly for quicker warm up for Fall weather. I don't have any cooling issues since I installed a new water pump and flushed out the rad.Temp gauge is steady where it should be. I probably should have changed out the heater core when I replaced the heater valve as I'm only getting Luke warm air from the heater.

[Mike W.]

So what is the actual purpose of a 71degree thermostat? Manufactured to accomplish what?

IMO they're kind of an anachronism from an earlier era. Cars ran well when carbs were on the rich side, emissions weren't an issue but metallurgy was and parts were soft and relatively short lived. Lower temperatures helped prolong life. But on a tough as nails M30 engine? Not an issue.

What's the purpose today? To make money.

[Falkenberg]

Maybe you do have an issue with the heater core. Or something else is hindering the flow of hot water. E12, at least here, has the reputation of being a very warm car in the winter.

Are both hoses connected to the heater core hot when you have the heating turned on?

Back in the days I has some overheating issues with the 2002 (or so I thought). So I fitted a 75 or 71 degree thermostat, I can't remember exactly. The effect was that, in the summer, the temp gauge went up, stopped before the normal running temperature (thermostat opening), and then after the radiator heated up (saturation), the temperature climbed up to whatever it used to be with the old thermostat.
And the lack of heat in the winter was noticeable.

[Mike W.]

Maybe you do have an issue with the heater core. Or something else is hindering the flow of hot water. E12, at least here, has the reputation of being a very warm car in the winter.

Agreed. My E12 has a better and faster acting heater than my E36 or E39. And with a new heater core it would be astounding.