Long enough to get the oil up to about 230F for 10 to 15 minutes should do it.
In this climate of the seaside communities of the PugetSound it takes about 8 or 9 miles to get to 180F, getting to 230F would take 40 mile trip if it ever got that high during the winter.
How far, on average, do you all drive when you start the MOG?
