To use a carburetor on a 302 that originally had throttle-body injection, you'd essentially need to replace a considerable amount of the intake system and potentially other components:
1. Intake Manifold: The most crucial change. You'll need a new intake manifold specifically designed for a carburetor. The EFI manifold won't work.
2. Carburetion System: You'll need a carburetor appropriate for the 302's displacement and application (performance, daily driver, etc.), as well as the necessary linkage, fuel lines, and fuel pump (likely a mechanical fuel pump instead of the EFI system's electric pump).
3. Distributor: Depending on the original setup, you may need a different distributor, as some EFI systems use a different ignition system than traditional distributors.
4. Fuel System: The entire fuel delivery system needs to be changed. You'll require new fuel lines, a mechanical fuel pump (mounted on the engine block), and a fuel filter.
5. Computer and Wiring Harness: The engine computer and related wiring harness associated with the EFI system will be completely unnecessary and need to be removed.
6. Other Components: You might need to adjust or replace other components such as the air cleaner, PCV system, and possibly even the valve covers.
In short: This is a major engine overhaul, not a simple swap. It requires significant mechanical knowledge, specialized tools, and the correct parts. It's not a project for a novice mechanic. If you lack extensive experience with engine building and carburetor systems, it's best to seek professional help or consider a different project. The cost of parts and labor could easily exceed the value of the engine.
