1 The TTI C-Body headers feature 1 7/8 inch primary tubes and three inch collectors. The flanges at the collector and cylinder head are 3/8 inch thick, so warping or leakage is unlikely. They even added clearance where needed for spark plugs and header bolts. These headers are available in bare finish, ceramic coated, or with a polished ceramic coating. We chose the plain ceramic coating which gives a satin-nickel type finish.