does anyone know if headers will have a effect on srt8 passing emissions??? also, if anyone has headers on their gc srt8, is the exhaust much louder and uncomfortable/annoying compared to stock exhaust???

Just headers shouldn't make any difference.

I installed many headers before from exhaust manifolds,Makes very little sound difference almost unnoticable.Your going from a header to a header you will hear no difference your emissions will not be affected.Anyway my opinion is that SRT designed those headers through extent hours of testing to optimize the performance of that engine,Headers are a pain in the ass they leak they crack and they wont be under warranty( LABOR)you can spend alot of money and heartache for vey little or no difference.Supercharging or turbocharging or changing engine internals then you should take all of that into consideration,Headers, intake,exhaust, but stock ,SRT put in all the flow that engine needs you can probably run a 600hp motor through the stock intake and exhaust but everyone has a different need or opinion just letting you know through my experience.LATER.