i just put in a new header and figured out my performance cat was empty and all my sensors are black. I have a 2.5 pulley with stage two spark plugs, 60 lb injectors w/ harness, pcm retune, and three inch exhaust system. what could be the reason for it running to rich if i retuned the pcm?

 

A little rich in the cold weather is better I would think,Doesnt the cold air tend to lean the cars out.

Is the car misfiring because of the plugs fouling ?If not I dont think I would be to concerned.

 

Improper tune.
But since you have a tune already, check your lines hoses ect. Basic stuff first.

I was running rich with a 2.85" Pully and 42lb injectors....
Got dynoed,
Sent the data and pcm to Intense
they used the data to tune me.
sent it back
Dynoed again Much better. Everything runs great now