check the number on the bottom of your ECU... it's above the glovebox. then go to www.turnermotorsport.com
& look up the chips they have available & see if your car or ECU # is listed.... i dont think you have a removable chip, but it's worth a shot.
if you do'nt ahve a removable chip, i'm guessing you will probably be able to swap ECU's w/ a later 318i (NOT THE M42 318iS from '91) and get a chip for that ECU. that's what alot of '84 325e owners have to do