I will be replacing my helmholzt resonator equipped test pipes with a pair of ARK R-spec high flow cats in a couple of days. I'm currently running a pair of O2 bung extensions on each test pipe, and still occasionally have both sensor 2 slow response CELs show up (PO159 and PO153) after finding and repairing both intake leaks (loose PCV connection on the K&N intake tubes) and exhaust leaks (due to test pipe weld cracks). Before these repairs I was getting these CELs in as quickly as 50 miles but are still getting them after 250-350 miles, and am quite sure that there are currently no leaks present. When I bought the car the test pipes with the dual bungs were already in place, and I have not tried to run the car to see what would result if I were to eliminate one or both extensions. I'm a newbie with these cars, and as far as I know the double bungs could be causing the CELS in the first place!
My question is can anyone suggest if I should install one or two sensor extensions per side on the new cats or leave them off completely to start off with? Thanks in advance for any response...........

 

Maybe my original post was confusing. I'm sure there are several folks out there that have installed ARK high flow cats on their cars. I'm looking for advice from you guys concerning if I should install my O2 sensors without any bung extensions, or one, or two inline in order to avoid future CELs.