Thermostat - Does opening temperature matter? Options

[woodst]

Hello!
I am rebuilding a frozen 1.8 engine and found a thermostat with an opening temperature of 90°C in it. It works fine - but for the stock engine an opening temperature of 65-70°C is recommended

Does it matter? New ones are hard to find or quite expensive.

I won't drive the car in winter but we have mostly intermediate temperatures at about 20°C. In summer it's actually pretty hot >30°C. Thanks to global warming...

BTW: I want to keep my flaps. There are lots of discussions whether they are useful or not. Please do not go into this again. I want them installed.

Cheers!
Malte

[Bartlett 914]

Hello!
I am rebuilding a frozen 1.8 engine and found a thermostat with an opening temperature of 90°C in it. It works fine - but for the stock engine an opening temperature of 65-70°C is recommended

Does it matter? New ones are hard to find or quite expensive.

I won't drive the car in winter but we have mostly intermediate temperatures at about 20°C. In summer it's actually pretty hot >30°C. Thanks to global warming...

BTW: I want to keep my flaps. There are lots of discussions whether they are useful or not. Please do not go into this again. I want them installed.

Cheers!
Malte

You are correct about the flaps. They are important and the motor will cool better with them in place. The thermostat only helps when the motor is cold and allows the motor to warm up a little faster. I suppose you could install the thermostat with the cable a little loose. You just want to make sure that the thermostat expands enough that the flaps are fully in the relaxed state (as if the cable was disconnected) when warm. Here is an informative link

Thermostats explained

[woodst]

Thanks, Mark for your help!
I know the mentioned article and that's why I ask for the different opening temperatures. I would never had noticed there are different types around....

If I understand you right, I can go with the 90° thermostat and the engine will warm up more quickly. That's it?
Or does it mean my engine will run on a higher temperature level, because the flaps will start to open approx. 20°C later? I don't know anything about the normal air flow temperature.
Maybe, it's far beyond 90° and there will be no restriction using another thermostat with higher opening value.

Should I convert a Type 1 thermostat? These are still available and pretty cheap. But they look completely different.... They actually use a coil to actuate the flaps instead of the "discs" of the original one.

I just want to get right....

Cheers!
Malte