You can a couple of different route to solve the notorious gear "hunting" that 84s have.
<- Inexpensive route ($30)->
You can buy a shift kit thingy that Ecklers or Corvette Central sell and it bypasses something and something else happens to something and then it shifts smoothly.
<- More expensive but more improvement route ($120)->
You can buy a Hypertech chip (I got a stage II) and it will solve the problem as well (as stated by VTvete). With the Hypertech chip you will have to run high octane fuel because it advances the timing which, with lo-'tane fuel, will result in pinging on WOT.
The driveability increased dramatically with the chip and I personally felt a little more throttle response and power, though a lot of people report it does nothing (as far as power goes).
Oh yeah, GET A 85+ FUEL PUMP! Sooner or later the stock 84 will start to suck. You will floor it and then about 50 yards into your furious acceleration, pbbbbpbpbpthhhh, it'l feel like an anchor was thrown out. The stock 84 pump cant keep the fuel pressure and it is a relativley inexpensive ($110) and easy (1/2 ~ 1-1/2 hour) job.
If you want some of my insight on the pump installation, go to
http://enrich.sdsc.edu/downloadables/fuelPump84inst.doc
It is kinda a step by step I did for another member about a month ago. Not entirely accurate but it was to the best of my reccolection from the project I did about 7 months ago.