off road x-pipehp gains?
does anyone know what the hp gains of replacing the factory cats with O/R x-pipe? I just cut windows in the top of the factory cats and dug out all the catylist and welded it back.
I know the cats on the S197 are better flowing than the older models, so did I just make the car sound better, or did I pick up any hp?
2006 Mustang GT lots of mods ex wife has it
1979 corvette stingray #'s matching 47K org. miles
1970Chevelle SS 454 big block Old School 500hp Sold