The factory exhaust architecture on the Up! GTI subdues the characterful three-cylinder thrum, while restrictive catalytic converters and gasoline particulate filters limit exhaust gas velocity. Removing these bottlenecks with high-flow Exhaust Downpipes drastically improves turbo spool times and reduces backpressure. For later models, GPF-back exhausts bypass the restrictive particulate filters, whilst complete Turbo-Back Exhausts offer the ultimate flow upgrade. Pairing these components with a Cat-Back Exhausts system completely transforms the acoustic signature of the vehicle.