Hi Lee
I would get the set up checked if I were you, and make sure the ECU has not been chipped. Obviously with any kinds of engine mods, there will be a difference, but you should still be able to tune the engine to within specified, or legal limits.
If you go to Rubjonnies digifant set up page, there is all the info you need to do a good job. The Haynes manual is also very comprehensive.