I'm guessing that's F not C - In Canada we all have block heater for our vehicles - I've often pondered putting a magnetic block heater on my UTV but they are hard to plug in when out in the bush
I've never had an issue with the P500 and -20c starting.
Does it not start in the cold or why do you ask?
Thanks
Magnetic won’t do much with all aluminum engine blocks.
Ovo