I had the Clubsport upgrade done in 2018. Each year when the emissions test is done against the clock between 2500 & 3000rpm it is always marginal. It usually takes 3 or 4 attempts, and as the cat gets hotter the emissions slowly reduce.
My manifold & cat are wrapped, but to be honest it is still marginal. Your tickover shouldn't be rough, so get the O2 sensors cleaned. If you decide to replace the sensors, they need an extension to the leads.
I had a recent conversation with a GDI owner with rough running, and although this is not a fix, he discovered that by unplugging the upstream sensor, the idle improved. His upstream was sooted up and so he replaced it.
When I replaced my exhaust, my upstream sensor was clean, but the downstream sensor after the cat was sooted up. That makes no sense to me but is apparently due to the cat combusting what is left over in the exhaust.
DaveW '05 Red Roadster S1 '16 Yellow (Not the only) Narrow AR GDI Plus 4
