Not related to a specific car, I am interested in the growing tendency for dual exhausts. In my youth, they were present on some luxury or high performance cars. But they are increasingly common, even on modest cars. Do they really have a signifiant function? Are they just for decoration? Are they advantageous? Thanks.
Dual exhausts help a car run more efficiently. Think of an engine as breathing. It “inhales” through the throttle body and “exhales” through the exhaust. A larger exhaust makes it easier to “exhale” by creating less resistance.
A combination of both of your theories. Dual exhaust will provide HP gains at higher RPMs. I added dual exhaust and different bumper cover when my car was rear ended- -purely for appearance.
Many cars today have dual exhausts purely as decoration. A single pipe come from the engine and dual exhaust tips from the muffler.
Real dual exhausts do have a function. An engine is basically just an air pump. The more air you get in AND back out, the more power you can make. That said, a 3.5 inch single exhaust flows as well as dual 2.5 pipes, but fitting an exhaust pipe that large under most cars is impossible. So duals it is!