Took off CATPipe And tried to look down it with my crappy borescope on my iPhone. It was pretty tough to figure out anything from that. So I threw a ping-pong ball down the pipe and it stopped about 18 inches away from the flange. But to me it doesn’t seem like such a huge restriction especially when I look at the picture of the exterior of the pipe with the ping-pong ball laying next to it for reference.
