Yes I know it is 25 degrees, but I just rebuilt my engine, hydraulic lifters, solid guides, modified with modern stem seals, late crank without sludge traps, high volume oil pump..modern 16 inch firestone (tradition) radials on stock rims....my little hot water heater working like crazy..it's almost heaven..Ok old timers, do you open the cowl vent letting the air "ram" into the heater thus increasing heat flow?? or were you just kinda cold in the old days?? I may need underseat heaters... jeff lzoc 1232 sylvania oh