From all of the dyno testing I have seen posted on the various forums, these do not improve performance much if at all.
On 2001-06-26 22:46, Zippy spewed forth this drivel:
Suggest Corsa or B& B after market exhaust system! Love the sound of my Corsa Indies!
Zippy /phpBB/images/smiles/icon_smile.gif /phpBB/images/smiles/icon_smile.gif