I've found a cash for clunkers 1994 LT1 Z28 @ a local pick-a-part with the computer, relays, etc. still on it. I'm considering getting the underhood computer(on the pass. wheel well) as a spare. Good idea or not? Any ideas on fair price? I don't know the proper term for it (maybe PCM) cuz I'm learning my way around my own '94 LT1 Z28, and don't know how to test to see if it's good. All feedback is appreciated folks..

 

If both yours and the donor are stock, both have the same transmission, gearing, and tire size. They should be interchangeable. Otherwise you will need to get the new one tuned at a cost (add $65-125.00) . The junk yard unit should go for $25-75.00 depending on your location. There is no way to easily test a PCM without bench equipment, ya need to put it in your car and make sure it runs OK. Make sure they take it back if it's no good, otherwise you can buy a used one programmed to your car and guaranteed on E-Bay.

 

It is called a Powertrain Control Module, or PCM. It is the computer.
I found several for ~$50 shipped.
Tunercat and a cable will allow you to put any tune it that you want, but they will cost, although you can find tunes for free.
Datamaster and VEMaster are virtually free for tuning adjustments.

 

Unless you are going to be DIY tuning your computer you have no need for a spare.

They can be had for about $50.