Evening all. First time on this site so please bare with me.Im going to collect an a3 2004 sportback 2.0 TFSi Quattro on Thursday after my mondeo st220 was written off 10 days ago. I’ve never owned an Audi so don’t know what to expect but looking forward to it. I’ve done a little research into tuning and I’m led to believe a full turbo back sports cat system is the best base for any future mods. However, I’ve just seen the price of these systems and literally sh*t my pants. So quick question, how much more power could I realistically expect from a CAI plus map on 99 Ron? Any advice would be most welcome. Cheers