Does a new exhaust really add Horsepower

Are we talking 4 or 6 cyls here? 3.5s have collectors/headers cast into cylinder heads. Only one exhaust pipe coming out of heads

 

Ahh yes, the "stickers make horsepower" joke out in full force. Every time I see that I think its some 16yr old kid thinking hes funny or some old ass guy that just learned to internet and thinks this joke is the rage all the kids are talking about. Cringe.

 

Aw damn, that’s a shame.

 

seems odd that nice tuned headers and a super cool exhaust would not make some difference

 

Because we dont have headers. Look at that single pipe coming out of the motor

 

there ya go, problem solved, need headers