I just read on SLP's website that their long tube headers are not street legal, but I've read a couple times on this site that if you get headers to get longtubes with it because they're much better. What are long tubes and what are headers btw?

Oh and here's what SLP says.
Q: WHY AREN'T SLP LONG-TUBE HEADERS LEGAL FOR STREET USE?
A: THE LONG-TUBE DESIGN REQUIRES THAT THE CATALYTIC CONVERTERS BE RELOCATED FARTHER AFT IN THE EXHAUST SYSTEM. REMOVING OR RELOCATING THE CATALYTIC CONVERTERS RENDERS ANY VEHICLE ILLEGAL FOR STREET USE UNDER FEDERAL LAW.