Hello,
I have the TORS underneath and removed the original airfilter and placed triple K&N Filters to give the engine more air.
If you replace the original exhaust for TORS or D&D's you will need another tune.
You can find them and replace it by using TuneEcu.( free software)
I did a Dyno run to make sure that the engine is tuned to be perfect.
The TOR's or D&D's together with replacing the original airbox for the 3 K&N filters as well the different tune ( better to do a dyno run) will give you a total different Bike.
Much more power and much more torque again. ( ask yourself if you need it?)
Also less milage per Gallon because of the tune etc.
On this forum is load of information available about it.
Our German member and fellow Captain Hardy has a site and placed movies on You tube where you can read and see how to replace the airfilter etc.
Tuning
Triumph Rocket III Drosselklappen Secondaries - YouTube
I will stay away from the auction on the D&D's to avois driving up the price.
good luck.
hans ( Holland)