RK-Tunes Catless F90 downpies eliminate the heavy and restrictive catalytic converters in the factory exhaust system. By eliminating the catalytic converters, your turbos can breathe more efficiently which reduces back-pressure. This reduction in back-pressure creates a faster and more audible turbo spool, a deeper and aggressive exhaust note, and most importantly, an Instant 30WHP+ WHP gain.
*Most companies downpipes are missing some or all of the factory brackets. We have seen this creates vibrations and the ECU will pull iginition timing thinking it is seeing knock / detonation which will make the car lose power. Our downpipes have every factory braket and fit like stock.
*Most companies use a larger cheaper flex section that will rub against the transmission. Our downpipes use an OEM style flex section.
Removing the primary cats will cause a check engine light and will require tuning or a spacer to fix the light.
Seconday cat delete will not cause a check engine light and requires no tuning changes.