2000 Audi TT Quattro is about to have 3" downpipe installed...do I need another tune?

[HurtlockerTT]

So I have a 2000 Audi TT Quattro and just got ahold of a xs-power 3" catted downpipe that im about to have installed...

The install will result in the twin catalytic converters being removed and replaced by a single larger cat further down the exhaust.

When I built my STi last time I did the downpipe before having an overall tune done but this time I already have the APR Stage 1 Flash and Im wondering if after the downpipe and catalytic converter is replaced will I need another tune again or should the APR Stage 1 be sufficient.

Ive searched the hell out of the forums and cant seem to find information on this and was wondering if possibly anybody else went through this scenario or if I could get the public opinion.

[HurtlockerTT]

So I had the downpipe and catalytic converter installed today and it sounds amazing compared to the old piping/setup. Ive only driven it about 25 miles since the install and havent noticed any negative issues yet. The 02 sensors seem to be reading the setup correctly so far and i havent thrown any CELs yet. I dont know if its just me and sort of placebo effect or not but the car seems to pull a bit harder and according to my boost gauge, I gained around 2.5 to 3 pounds under WOT.

[MetalMan]

Gains are good!
25miles may not be enough to trigger a CEL due to "catalyst below threshold" type of fault code, if you will get one. Might be 40-50 miles, but time will tell.
Enjoy it!

[HurtlockerTT]

i broke 100 miles with the pipe today and still no CELs but i do notice vibration coming from the pipe vibrating against the car...xs power didnt have any kind of warning against this but when i looked at APRs 3" dp it says that its recommened to switch over to dogbone motormounts so i guess those will be coming in the near future.