[cobraduke]

Mine (header's directly to one high flow cat to side pipe on same side, straight shot) are after market. Probably done by previous owner as a result of the cracking and needing to pass California smog. As far as I can tell, there were only two factory configurations, one crossing under with the four cats and one looping forward, same side with four cats (?). I believe the four cats (two per side) were Ford parts as used with the 5.0 EFI motors and simplified the emissions certification. The plumping was unique to Excalibur to fit the chassis. I have photos of the cross over system, but none of the same side original system. I'd sure like to get some of those for the record as I think both systems had cracking problems due to the weight of the plumbing and cats hanging between the heads and the side pipes, vibration and solid side pipe mounting. This means as time passes, fewer and fewer will remain in place and the opportunity to document how the original systems looked will diminish.

I had to have the header on one side of mine welded for a crack at the collector between two pipes. It may have been due to vibration caused by the fairly stiff side pipe mounting or a faulty weld on the header. If it cracks again, I'll know.

Mike