For a performance upgrade your going to need to upgrade the whole exhaust, not just the muffler. The sticked threads at the top of this section contain all the information you need about the bolt on performance upgrades for your car.
And just FYI, our ECUs cannot be "chipped". They must be flashed with a SCT device with a custom tune.
2012 Fusion SE 3.0L V6
'86 XR4Ti ; 2.3L Turbo, 15psi
1988 F150 Custom
'07 ST ; formally bewst'd - R.I.P
D23 Crew: #07