Engine seems hotter than normal

[EklipseRS]

Ok,
I'm not much of a performance kinda guy. Just trying to get the best as needed without wasting money. All I have is Iceman, RT cat, Screaming demon coil, 8mm wires, and Bosch +4. Anyways, RT cat was the latest thing I changed. Just lately, I'm noticing, that my temperature gauge had been rising a little, like to 1/4 between the middle and Hot, but it does cool down (unless I stay in th 4k for long time, then it stay steady at right above middle line). Seems to do that when I only when engine runs at =>4k rpm, cruising at 75 miles/hour keeps it steady at right below the middle. I checked the cooling system and everything seems to work correctly, I'm thinking it's something causing my engine to run hotter. Could I be running too rich? Does someone have an idea?
Thanks

 

[1stGenRocks]

not sure if this would cause the problem you're having but the only thing i see about your setup that i dont like is the bosch 4's turbo cars dont like platinum plugs since they usually make knock from the platinum staying hot and predetonating. put in some ngk bpr6es and see if the problems goes away.
the ngk's are cheaper then bosch too

 

[beat90tsi]

His car isn't a turbo, so are the plat plugs really the problem? Do the BPR6ES fit the 420A?

 

[EklipseRS]

sounds like I'm running rich during acceleration though! And seems to be like that more at higher altitudes, at lower attitudes it stays very close to middle. Think it's something to do with my MAP sensor?