Duplex stainless-steel exhaust system with 1 × 100 mm outlets on the left and right for Volvo S60 II/V60 T3/T4/T5, all 2WD, type F — TA Technix

A complete exhaust system replaces everything downstream of the catalytic converter. Its main effect is sound: less-restricted mufflers, a more pronounced low tone, and a sharper-sounding increase in revs. In terms of power, the gain exists but remains modest on a stock engine because the restriction in a standard engine is mainly upstream - the catalytic converter and downpipe.

The second effect, less often promoted but more lasting: weight and durability. A stainless steel exhaust does not rust, can still be removed ten years from now, and weighs less than an original aluminized-steel exhaust. On a car you plan to keep, it is the part you only install once.