So I had a block heater installed recently- can't use it yet for lack of an outside outlet- but I was wondering what kind of time is required for this to warm up the block (as much as it is capable of)? Obviously this depends on the outside temperature, so let's say it's zero fahrenheit outside, am I looking at overnight? an hour? half-hour? 10 minutes?
If it matters it's an '87 900S (NA 2.0L 4-cylinder) w/Saab block heater. I just replaced the battery and have been taking it inside at night- this appears to be a dramatic improvement over last winter all by itself.
TIA