2018 civic si sedan

So I'm looking into getting the Aeroflow dynamics rear diffuser. My issue is I have the MAPerformance exhaust system on an im not sure if the pipes are going to fit in the gap with the diffuser on. Tried asking the company directly but couldn't get a straight answer so im turnin to the honda...

hello everyone im looking to trade my MagnaFlow catback exhaust for my civic si sedan for the stock exhaust, and Money I paid 875$ for the exhaust looking to get 600$ and the stock exhaust. im located in Los Angeles , let me know! the exhaust is only 3 weeks old, probably 100 miles on them!

SO, I live in Philly and i'm looking for a few things for my 2018 Civic SI Sedan (black). Looking for: HFP Wheels (matte black) PRL Catted downpipe / front pipe PRL/Injen cold air intake (whatever sounds better with similar horsepower improvement) Hondata/Ktuner tuning - i have no idea how to...