I recently arrived home from a 3 week 6000 mile trip pulling our fifth wheel and noticed that the compressor side of the turbo housing is now a toasted brown color where it was silver before leaving on the trip. Is this normal and nothing to worry about? I have installed Rip's 4" exhaust w/muffler, A BHAF with no sheild, and an Edge EZ. I started with the EZ on the highest fueling level and about 1000 miles into the trip switched it to the lowest fueling level to try and keep the EGT numbers a little lower while towing through the hills of Montana. Any info would be great.