The catalytic converter pipe on my '87 744 has hit the center support bracket since I've owned the car. It used to only knock after hitting bumps or potholes. I recently had the trans mount replaced and now the converter pipe hits over and over. I got under the car last night and had a good look. The exhaust hangers are decent. The cat has only the smallest amount of clearance under the bracket. The bend in this pipe puts the lowest point on the cat past the support bracket. I can't tell if this is the original cat (or even a Volvo replacement). Is it possible I've got a replacement cat with crappy bends? Any other ideas to eliminate this interference?