Dual exhausts on 75 Scamp 318

The same manual also states that some 318 engines are also only equipped with an air pump only (much like the 360 Dusters). That explains why my '75 318 Scamp never came with a catalytic convertor.

Depending on how much $$ you want to spend, you could get an axhaust shop to make a dual system for you or buy one pre-done and mandrel bent. When I swapped the single exhaust for the duals on mine, I had the shop make it custom from the manifolds back.

If your state has annual emission tests, then you may need to rethink your strategy if you remove your cat and your car doesn't have an air pump.