I know there is a thread already asking about a V6 Nelson tune, but I have a couple other questions. I have a 2003 Silverado RCSB with a 4.3/5spd with a cold air intake, flowmaster 40 dumped, and some Denso Iridium plugs. Would a Nelson tune (or any custom tune) help much considering my shifting and torque managment can't be changed? How much difference would I see? Or how about a set of E-fans? Would that help much at all?