This is probably gonna sound stupid, but what exactly does the computer do with the carb? If it only regulates the air/fuel mixture and idle, can you unplug the carb from the computer and adjust the idle and air/fuel mixture manually?

In a word, no. The ECM does regulate the A/F mix from idle through about 1/2 throttle. If you disconnect it, it goes full-rich. The components inside the carb however, do not lend themselves to maunal tinkering. They are designed to be cycled quickly between open and closed by the ECM. You can't just set them "in the middle somewhere" and get an in-between air/fuel mix.

And, the ECM does not directly control the idle speed. That is all mechanical adjustment.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4, 2300 stall TC. Ported World 305 heads, Crane PowerMax 2050 cam. ZZ3/4 intake, oil pump, pan & baffle. Accel HEI SuperCoil & module. Hooker 2055 headers, 3" Catco cat & 3" catback w/dual-opposite Flowmaster 80. 2.93 limited slip. Spohn SFCs waiting to be installed. AMSOIL syn lubes bumper-to-bumper. Daily year-round driver. Best ET, speed TBD...
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