O.K.- so about three months ago I dyno'd my 2004 Mach 1 when it was bone stock except for a SLP catback and was pleased to get 283rwhp and 310lb/ft.
Today I had it dyno'd again- this time it has the SLP catback, a Magnaflow off-road Xpipe, a PHP intake spacer and a Diablo Predator Handheld...