I pulled the motor out of the race car 1st week of December it was right around 40 degrees in the garage, anything lower than that i cant seem to function. Worked outside for the city for 33 yrs. sometimes in sub-zero weather repairing watermain breaks or what ever was required to do at that time and it never seemed to bother me. Now that i'm 58 and been retired for 3 yrs i've gotten use to stayin in the warm house near the fireplace. Next year there is a gas furnace in the works for my garage.