Here my bang for buck power mods
Gruppe-s Header/overpipe $475
pretty darn good value and well made
http://www.ft86club.com/forums/showthread.php?t=81839
Buy a Tactrix cable $170
http://www.tactrix.com/
Bit of reading and talking to the right people and you will likely get a good E85 and petrol tunes to suit tune for about $50-100 or even free if you do it yourself :-)
total about $700 for header tuning device and tunes E85 and Petrol :-)