[db2022cs]

So I will be eventually going with headers on the car. I don't want to have to deal with headaches of emissions and inspections so what would be the option to go with when adding headers. I see the option of catless which would just introduce a huge headache, headers with OEM cats, and headers with Green cats. Are the green cats just high flow cats that will do just enough to not cause any emissions headaches? Will the OEM cats with headers still add a decent amount of sound? I will be keeping the NPP exhaust and I will also be getting E85 and a tune. Do I need to get a cold air intake with this setup? What would be the gain with this setup of headers, tune, e85 with CAI vs no CAI. TIA.

[arpad_m]

The headaches depend on what kind of emissions testing Wake County does where you live. If they have undercar cameras, you can't do anything to the stock setup; if they do tailpipe sniffing, you don't want to go catless, you can use either OEM or green cats. These will also be fine if they only do OBD-II, and in this case technically you could go catless, but why be a d**k to everyone else and give a reason for the karens to try and ban all mods, right?

No matter the inspection, even if the county only does OBD-II readiness checks, your tuner needs to make sure no permanent "background" codes would be set, as those can be retrieved even if you clear codes after installation.

I have green cats with the NPP exhaust as well as flex fuel, and boy, did those headers add volume, especially at WOT.

I'll defer to the professionals as to how much you would gain with or without an intake with the planned setup.

[Judy1le]

Originally Posted by db2022cs

So I will be eventually going with headers on the car. I don't want to have to deal with headaches of emissions and inspections so what would be the option to go with when adding headers. I see the option of catless which would just introduce a huge headache, headers with OEM cats, and headers with Green cats. Are the green cats just high flow cats that will do just enough to not cause any emissions headaches? Will the OEM cats with headers still add a decent amount of sound? I will be keeping the NPP exhaust and I will also be getting E85 and a tune. Do I need to get a cold air intake with this setup? What would be the gain with this setup of headers, tune, e85 with CAI vs no CAI. TIA.

Pitt county here. It looks like Wake does the visual inspection labelled as “visual safety/tamper inspection” in addition to the onboard diagnostics so what the fine details of what that entails and if you could get away with headers and greencats, I am not sure. Hopefully others chime in.