stupid question from a curious friend

[blink182sk8rm]

my friend jason wants to kno what would happen if you didnt use a muffler or a pipe on a ped

[Erick]

It would be super loud and not very fast because of the back presure.

[blink182sk8rm]

now im wondering whats back pressure

[Erick]

I think its where the air cant exit the cylinder very good and slows down the piston.I think