Sorry to revive an old thread, but:
I recently installed the akrapovic evo xpipe (primary cats removed, secondary and resonators still there).
I had the install done about 2 weeks ago.
I had my first "backfire" today. Sounded real fun!
Worth noting, I filled up with Shells V-Power+ for the first time in a year (before I had the akra xpipe installed) yesterday. Maybe this has something to do with it? Who knows.
Sounded great though
