Ask away mate!
tuning 8v's depends pretty much on exactly what you want it to do, bearing in mind that you have to sacrifice something.
if its just for some quick overtakes, then improving the 8v's spin-up time with some decent porting of intake and exhausts ports is a good move, the rest depends on what fuel injection and ignition systems you have before changing the shape of the combustion chambers can be considered, a rally-spec exhaust manifold is on the cards in this case but thats pretty much the only expensive part, others will be simple things like panel filters and maybe a ram intake for the airbox and so on.