223 degrees is a little elevated, but that can happen when you have higher ambient temps. I'll take a look next time I'm driving the Mustang and see what the cylinder head temp is running on the wife's car. Temps here in Alabama have been in the mid 90's as of late so we'll see how hot she's running. The norm is right where you referenced though which is 195° +/- 10°.I see temps for the head as high as 223 Fahrenheit in my mustang although it usually stays between 185 and 209 Fahrenheit most of the time . What's the norm for cylinder head temp? Also, does the heat affect the turbo more, as in does it hinder it?