Reply to "Modifying headers"

I had the same problem with a set of GTS headers I bought off of a guy with a GT5S. One side was slight ly off and the other side was a full third of a hole off.
I took a carbide burr and matched the port shape on the better side and then reshaped the tube and tig welded it. The Bad side I slotted the header bolt holes to move the port over. I had to weld more material on the flange because the slots went past the flange. Then I reshaped and welded the ports like on the other side. Its not perfect but it is much better.
Mike Drew was in town at the time an visiting the shop and he said that these were the worst headers that he had seen.
Mine were also very crude looking in the collector area so I cleaned that up also. I also had a fitting problem with the fuel tank shield so I had to put a small depresssion in the tube that runs by it.
Welding the pipes was tricky because of all the rust and contamination in the flange area that had accumulated between the tube and flange.
I tried to post pics of mine but this window wont let me do that. Good luck on your modifications