[pdonis]

I have a huge piece of cardboard blocking the entire radiator to stop air flow.

This won't make any difference unless the thermostat is open. If your temperature gauge is on "cold", you're not even close to the point where the thermostat will open if it's operating normally. Which raises the question: have you had your thermostat checked to make sure it's not stuck open?

[grecy]

> This won't make any difference unless the thermostat is open

Actually, it makes a huge difference as it stops an enormous amount of very cold air going through/around the radiator onto the engine. Everyone up here does it, else cars would not be warm enough to run properly.

> Have you had your thermostat checked to make sure it's not stuck open?

Of course. Everything works great in summer when it's ~+25C

To give you a better understanding of how cold -50C actually is, I can drive for an hour, get out and put my hand directly on the exhaust manifold of my 4-cyl East-West engine (exhaust at front for cooling) and it's only just warm to the touch.

It's cold. Very cold.

[pdonis]

-50C

Ah, that explains it. :-) I used to do cold weather testing when I worked as an automotive engineer; the coldest we ever tested at was -30 C, and there were plenty of test vehicles that didn't fully warm up at that temperature.