[Axle]

Define your idea of what decent horsepower is.

The thing is, to get decent horsepower out of it, you'll be spending $$$$. Back in the 80's, (aka my street racing days. And since I tend to look at it from a drag racing perspective) we had a handfull of guys who where diehard straight and slant 6 lovers. While the 6's did get meaner, they didn't stand a chance against the v8's. They would have been dollars ahead if they had left their I6 passion as a decorative peice in their garage and just swapped in a v8 with minor mods. Yes, they had unique rides, but their mouth went faster than their car. =-)

Without looking into it, which I should to be fair, is whats the pricing like for speed parts for a straight 6 these days? Headers still cost 2-3x what a v8 header set cost? Have you got an integrated head i6 or an older separate head/exhaust? Obviously to do anything with the integrated head unit, you'll either be swapping to the older head, or taking a very expensive aftermarket route.

Obviously I look at it from the go-fast side, if all you are after is a bit more pep, then some basics will get you there without putting you in the poor house, but it'll never give you v8 bang for the buck. Yeah, I'm v8 biased. Yes, I have also owned (inherited) a couple I6 powered cars. Utility-yes. Gofast-not quite.

Best thing I can say is figure out what you want to get out of it.
Grab a pencil and paper and work out the cost to do that vs swapping in a v8.

Alex.