Ford Fiesta zetec s backbox delete

[adamjudge6]

Hi guys, looking at getting a Ford Fiesta zetec s 1.0L

If I install a back box delete twin exit from EMP performance it may sound stupid but will it increase fuel consumption?

Thanks
Adam

[zsdom]

The back box itself wont increase consumption but you driving like a knob because you like the sound will though!

[Chris32345]

It's also a mot fail if your in the UK die to being significantly louder then standard