Tuesday, November 08, 2005 - 07:24 am, by: David Vaughan(Davidv)
A 30rwkw gain is available without fitting headers (and no drone, as Peter says). In fact, my exhaust retains the original resonator as well as the cats and exhaust manifold. Cost for that (including Unichip) was $1950 or $65/kw compared with $90/kw in Avin's example.
So, replacing headers and cats is not as cost effective for power gain as the other three changes (BFI, Unichip, muffler/strangler replacement) but if you want the extra power headers/cats provide, then it is cheaper to do them before the rest of the exhaust.