If it was running fine with the old Stage 1 Filter you should be fine with just changing to the new SE Filter. Chances are the prior owner compensated when the exhaust and filter was first changed.
If it was not and/or is not running well after the change I would suggest getting a tuner of your choice that will allow you to make changes if necessary at will and staying away from the Dealer Download/Flash.
I prefer the DynoJet Power Vision Tuner but there are many that will work as needed.
Welcome to the forum by the way...........
Last edited by Triplej; 02-18-2012 at 01:31 AM.