With the wiring that hacked up, I would have passed on that car.
Most 80's G bodies used the Computer Comand Control system (CCC). It was a computer system that controlled the air fuel mixture on the primary side of the carburetor, the ignition timing advance, the transmission lockup, EGR valve, and smog pump diverter valves. Later versions came with knock ignition retard and EVAP purge control. The Olds version of CCC was unique in that it also controlled the A/C. Every GM division used its own version of CCC. Olds was also very late in getting knock retard. The CCC is also all or nothing type system, deleting any part will result in it defaulting to limp mode. In limp mode, the fuel mixture defaults to full rich and loss of timing advance.
A computer controlled carb will have two computer plugs, one for the throttle position sensor and the other for the fuel / air mixture control solenoid. A computer controlled distributor will lack a vacuum advance can and instead will have a 4 wire plug for the computer advance.
Sadly many previous owners were ignorant about how CCC works and ended up butchering their engine bays in a vain hope of magically improving HP. Instead they just turned their cars into basketcases and after becoming fed up sell them to unsuspecting buyers. Its a pattern we see all too often.
Besides hacked up wiring, two other common problems are vacuum leaks and too much fuel pressure from poor quality fuel pumps. There is now software to allow you to datalog the CCC system with a smartphone. However, its no replacement for a analog dwell meter and Brainmaster scanner. Its a good idea to upgrade the original 1 wire O2 sensor to a heated 3 wire O2 sensor.
