camshafts

[NoHachi]

Damn...I wish I still had some sort of desk dyno software.. I could use the GT-suite software for a while, but the license from the racing team has expired.

Basically what you'd want with any upgrades to the engine is knowledge of what is happening inside the engine. I would highly recommend buying a cheap Wideband lambda setup to monitor AFR. Once you have a baseline and know where the car needs more fuel, then you can start tweaking the mixture. this can be done through a piggyback, fuelpressure regulator or other injectors, take your pick.
Cheap WBO2 sets are available from Tech edge or AEM, make sure to get one with a LOG function and possibilities to plugin a rpm and map/TPS signal!

Don't start by just throwing parts at the car! the list above is a pefect example of that. The exhaust is probably just fine, so is the head. Porting usually does more harm than good, its just masked by the fact that people make a lot of changes at once (aka power increase from cams).