OK so a bit of an update.
I have a SCT Livewire, 170 Thermostat, plugs, k&n filter, and 3 bar MAP all here.
I am looking to order downpipes, but I am now leaning more toward catless downpipes while leaving the remainder of the stock exhaust in place (including resonator and 3rd cat).
I know PPE catted downpipes keep the emissions system happy, but do the benefits of the catless pipes outweigh that? As far as preferences go, I like the sound you get from the turbos and the slightly increased exhaust note with the catless systems I have listened to. Beyond preferences, do catless pipes allow the turbos to spool faster at lower RPM? Does it keep them cooler? I know we are talking about 5HP overall, so I am not chasing power here. I just like the exhaust note of catless and seeing if there are other ancillary benefits.
I live in Michigan so emissions requirements aren't a concern and as far as I know there is no plan to change that any time soon.
Getting closer to putting this all together!
Thanks!
Don