I'm partial the the stick on oil pan heaters. I've got a 100watt for mine.I figure they work as well as a block heater but less invasive. They will do the same thing through natural convection. Being as the heat is at the bottom it will continue heating the entire engine. Plus the fact when you have a block heater it only warms the coolent (to a certin extent). With a pan heater the oil is the first thing to get warm and will prevent the thick oil cold start damage...Just my thoughts, Cambo