1. Remove TBI Components:
- Disconnect the battery.
- Remove the air cleaner assembly and throttle body.
- Disconnect the fuel lines and electrical connectors from the TBI unit.
- Remove the intake manifold with TBI attached.
2. Install Intake Manifold for Carburetor:
- Obtain an intake manifold compatible with a carburetor.
- Install the new intake manifold using appropriate gaskets.
3. Install Carburetor:
- Choose a carburetor suitable for your engine's performance goals and modifications.
- Mount the carburetor on the intake manifold and secure it with the appropriate bolts and gaskets.
- Connect the fuel lines to the carburetor.
4. Install HEI Distributor:
- Remove the existing distributor cap and rotor.
- Take out the old HEI distributor from the engine.
- Install the new HEI distributor per the manufacturer's instructions. Make sure to properly align the gear teeth.
5. Electrical Wiring:
- Connect the wiring from the HEI distributor to the ignition coil and other necessary ignition components. Refer to a wiring diagram for the correct connections.
6. Adjustments and Tuning:
- Install a compatible fuel pump for a carburetor setup.
- Adjust the carburetor's idle mixture and other parameters for proper air-fuel ratio and engine performance.
- Set the ignition timing according to the specifications for a carbureted engine.
7. Test and Fine-Tune:
- Reconnect the battery and start the engine.
- Check for leaks, vacuum issues, and any other irregularities in the engine operation.
- Fine-tune the carburetor, distributor timing, and other settings as needed to achieve optimal engine performance.
It is recommended to seek the assistance of a qualified mechanic or consult specific tutorials and manuals for your 87 Chevy 350 model when undertaking such modifications, as details may vary based on the specific vehicle's configuration.
