My 08 FLHTC has dealer installed Stage 1 (Screaming Eagle mufflers). If I change to true duals using my Screaming Eagle mufflers, will I need to have it retuned?
The stage 1 is designed to work with the SE parts. Once you change anything the flow is changed but the download will not be available for the true duals being they are not a SE part. Should use a TFI so you can tune yourself .