I have a 1985 irocz TPI 305, my question concerns changing the chip. Ive been told by parts stores that I would have upgrade my computor and prom for a chip to be effective.Also the computor connections, is there a cost effective way to achieve my goal ? A new cam shaft is in the plans after I solve this problem! Thanks!

i would look into other components prior to chiping it i have been told that the old system its on is not the best to upgrade, but you can do alot for it with just modifing the exuast and air intake. but i am running into an air intake issue right now i cant find an origanal air intake for my 85 Z. so i bid you good luck and be carefull. :beers:

Depends on if your engine is a speed density type (using a Manifold Absolute Pressure sensor) or a Mass Air Flow type. MAF systems will adapt to exahust intake and head upgrades which improve the volumetric efficiency. Speed desity types require tweaking. As far as I know, the ECM in your engine is an excellent unit and is probably the most tweaked ECM in use today. Check out http://www.thirdgen.org for more TPI / ECM related stuff than you can shake a stick at.