i have rk sport ground effects and wondering if would hurt the performance if i put dual exhaust on. if not do i have to make my own exhaust to have duals or is there a kit i can buy?

 

you can, you just need to run like 1.25 inch duals to match a 2.0 inch exhaust if your looking for an exact replica in power, or maybe 1.5 in

 

Tailpipe size, the piping behind the muffler, will not do anything for performance either way as its basicly just a tip and we all know tips do nothing but make it look good. So to answer your question NO it will not hurt anything but its not gonna help either, its just for looks. Post pics when you do it cause IMO duals look great!