Header Tube size.

when i built my engine i had the schumacher headers, i got them because they simply fit the best. i could get them in and out while the engine was in the car. i took them off because i wanted the 3" x pipe exhaust from tti so i ordered the complete exhaust from engine to bumper. the TTI are a bit spendy but they will be the last set i have to buy and will never have to worry about them.