Typically there is no maximum EGT for normally aspirated engines. Max EGT is applicable for turbocharged engines because turbos have a maximum allowable turbine inlet temperature (TIT).
It is usually best to ignore the absolute value of EGT readings since that value can vary significantly from variations in probe location and position. EGT readings are best used as a reference measurent to determine where you are running your engine (mixture wise) in relation to your peak EGT reading.