Hot Head PRO4 Engine Heater is design to provide the fastest 110 volt heating rate. To achieve this, we pioneered Low-mass, Low-volume, on-demand technology. Extensive testing proved race ready performance for all 4 cylinder automotive applications. Realize the heat output for any 110 volt plug in heater is about the same as a hair dryer. This, or any other 110 volt heater will leave peak engine power and readiness off the table. For large engines, such as V8s, see our purpose built, PRO unit. It is not offered in world power option.