The problem they have is they think a lower t-sta temp makes more power, it does but it is very little and not worth it for the increased wear and tear and lower gas mileage. It makes more power because it gets colder air into the engine witch is more dense so more total air (and corresponding fuel)molecules make it to the combustion chamber. I run mine hotter because I like MPGs smoother running and longer engine life. Whatever the factory chooses to run is a compromise. As for the factory gauges, they are showing over heating by 220 because they know that most people will not be stopped by the time it reaches a REAL critical temp unless you warn them long ahead of time, even the new cars are set up that way, can you really imagine that those metals in the engine are gonna somehow self destruct because they are 220 degrees? Is cast iron, aluminum, brass, bronze... gonna start melting at 220? Any decent oil will not be close to breaking down at that temp either and a 50 50 mix of ethylene glycol will not boil at 16 PSI either. Any one got one single good reason they would call it overheating at 220? witch piece is gonna get ruined at that temp?