What temperature does an engine block heater keep the block?

An engine block heater doesn't bring the engine block up to a specific temperature like, say, 180°F (82°C). Instead, it raises the temperature of the engine block *significantly* above the ambient temperature, typically by 30-50°F (approximately -1°C to 10°C). This makes starting easier in very cold weather. The exact temperature increase will depend on the outside temperature, the heater's wattage, and the length of time it's plugged in.