No sir it dose not am going through some warranty issues with my 2018 rxtx 300 and it has a free flow on it as well the dealer asked if I had the stock box and if I would please change it I did in 20 mins in the parking lot and that was that
Darren Rivenburg i wouldn't say more Horse power gains but quicker accel definitely on sport mode could feel the difference with the ristrictor on and the free flow.