As i said my understanding.... Not the expert.... But have seen packing material blown out.... And not because they were tryin to....

And yes i know colder ambirnt temps seen to cause exhaust to sound better and vehicle to generally run better... Colder air tends to lead to better atomization of fuel along with denser air charge.....so theoritcally denser air would lead to "better" exhaust tone, especially coupled with theoretically better engine performance....