Originally Posted by Shempi
What exactly is an ORP?
Off Road Pipe. Replaces the catalytic converter with essentially a straight through (but curvy) pipe. Not exactly legal, but if you don't have emissions testing you should be ok. Another option is a High Flow Cat, or HFC, which costs more, but still gives positive gains over the stock cat. And its legal (in most states/applications)
Mine: 2004 Subaru WRX Wagon: 116k, WRB
Gone: 2002 SVT, #1654
Hers: 2012 Focus Ti Sedan: 67k, SGM, Manual