That's to be expected. My 2.0 TSI VW CC with a Borla catback became a bit too much when I added a downpipe to it.
'98 Dinan/RMS stage 2+(VAC cams, CES Cutring etc)
'11 Saab 9-3 XWD tuned(wife)
'06 Saab 9-5 Combi 5mt tuned(Aero interior/Konis etc)