CoachG

iTrader: (4)

Greddy Evo2. Quiet at moderate RPM but a mean growl at WOT.

giumela

iTrader: (1)

Aps

lowkey

iTrader: (5)

If you want drone-less you need a resonator on the intermediate pipe.

WORKS has a modular 3” Turbo-Back that has a resonator. It’s modular, which means you can swap individual pieces like the down pipe, cat and intermediate pipe out for stock items. But, at the moment they only have 3 options for the axle back: either their axle-back pipe without a muffler, their “stealth” option which is the existing muffler with the internals opened up for better performance or the stock muffler. Apparently they are testing an axle-back option with a can but there is no word on when that will be available.

It looks to me like all the other catbacks with resonators narrow down to less than 3” where it meets the cat, except for the Vishnu standard (but it’s not modular).

Here’s a list if catbacks that have resonators:
AMS
RMR (Not RNR)
Turbo XS
Greddy EVO2
Invidia