Head Temp higher than usual

I have an LS/VTEC engine on a 3G integra. It is a 96 B18B block with a 97 GSR head, ITR intake manifold, JG TB, adj sprockets, R1 header, ITR pistons. I have noticed lately that the Cylinder head temperature gauge is a higher than what it used to be. (it used to run around 190 degrees, now it goes up to 215 or 220 degrees. I also noticed that after the temp goes anywhere passed the 190 degrees mark it start to knock a little and as it goes one it get louder unless I press the gas and get more fuel into the chamber. Since I have a PMS I opted for adding more fuel and retarding the timing a little. It work but since the ignition went back it is lacking power. I don’t know what else to do to it. If anyone else had the same problem and found a solution to it please let me know. My next thing would be an oil cooler. The factory temperature gauge runs about the same (just a little bit higher, but this gauges are not as detailed as the autometers). Thanks for taking your time reading this!