Is it the picture or is the rear section actually smaller in diameter than the header pipes? That certainly runs counter to what I would have thought.
Must be just the perspective, the exit diameter is about 3"
It It looks like my Hooker header
That's what my friend guessed when I first showed that picture.
"Big D" used to sell them. I had one on a 1972 model.
If Jack sold them they must have worked. It's a bit rough between 4 and 5K, but it screams on the top end.