I know it's an old thread!!!

Rang an exhaust guy today to inquire about the cost of a standard exhaust for a HZ 308.
He told me that they ran 1 7/8" twin pipes into a 1 5/8" single, through a 1 5/8" muffler and then out through a 1 5/8" tailpipe.
When i asked him about how small the system was, his reply was that they used smaller pipes for more torque back in the day.

My question is:
If it ran a so small system, wouldn't it restrict the flow of the exhaust?
Also i thought that a that it would have been twin a single 1 5/8" THEN into a 1 7/8" collector?