Ok ive been pouring through the fwd deville forum about the operation tempeture for the car above. Found plenty on the norths but because is craped on me it was replaced with the same 4.9 pfi that is oem with the exception of its build material. I hope it will prove worth its replacment hassel. But im told that 190 is where it needs to be by a close source, but was not sure because i would assume that the aluminum at 210 .( lighter metal) would not run as hot as a steel block might. As It is , it will run 223 . but im told that will warp its piston heads . it might be different because its an engine but steel normaly wont warp untill 400plus. (No reason to ever get that hot). Alas thats why im here seeking advive from those more adept than myself. Any wisdom would be much appreciated because now im not driving it because of being safe than sorry with a warped engine thats brand new. Would a cooling system beyond the oem be in order because of the material change? Something more After Market? Suggestions? Much appreciated guys.