Ford Focus MagnaFlow Catback Put some muscle back into the domestic side of the sport compact market wiht a MagnaFlow Focus cat-back system. You can get a lot of power out of a 2.0L engine with the right comination of modifications. MagnaFlow's system uses 2.25" fast-flowing mandrel-bent stainless steel tubing, a straight-through MagnaFlow Performance Muffler and a 4" polished stainless steel rear exit "Sport Compact" tip. MagnaFlow's Focus system pulled an extra 5.4 horsepower and 7.5 ft-lbs of torque on the dyno.