RE: Carbon build up
The new NMP header is supposed to be a "cooling" header, I have this w/ about 10 gallons through it and only enough carbon to turn it black. PM 30%
I wonder if a higher temp tends to cook off the lube thats in the header, does the header carbon up at the widest part as well as the narrowest? Seams like the narrowest part of the header would be the hottest.