1st get the extractors/exhaust done, as most mods after that will rquire it anyway.
So far, the best quotes i have got are from Quikfit balcatta, bat there are other stores closer to you.
Im tossing up wether to go Pacremaker race series, or Lukey headers. I think paceys are close to $400, lukeys nearer to $300. But i havent got any quotes for a while.
2.5" mandrel bent exhausts start at around $240. I had a lukey system on my ea, sounded good. But will probably get a berkley staright thorough system on my EB. Personalt taste really.
Then make a home job Cold Air Intake. Do a search for what others have done.
After that, id suggest a cam from wade. Go to inline 6 forums and check out the cams thread. Just go to the last page or 2 (there are over 500 posts)
Probably cost WAers $120 + $15-20 shipping either way.
And get some adjustable gear from crow for around $200.
If your cars auto go to mechanicalforums.com(.au??), register, and check out the 'electronic shift kits'. Have to be logged on to view.
Can make your own for like $20, and get wheel spin into 2nd gear
Then if still not enough go for you. Change the diff gears. 3.45 (xr6) are pretty common.
If u got a auto, 3.7s, or manual 3.9s, are probably the best matched.
After that u are looking at head work, and bigger matched cams, which costs a bit of $$.
So ill leave it at that for the moment.