Fuel Lines: You will likely need new fuel lines, as the ones for the 2-barrel carburetor may not fit or be compatible with the 4-barrel carburetor. You will need fuel lines that can handle the increased fuel flow required for the 4-barrel carburetor.
Air Cleaner: You will need an air cleaner assembly that is compatible with a 4-barrel carburetor. The air cleaner assembly will help ensure proper air intake for the engine.
Throttle Linkage: Depending on the throttle setup on your 350 Chevy engine, you may need new throttle linkage to accommodate the 4-barrel carburetor. This will allow you to control the airflow into the engine through the carburetor.
Choke Control: If your original 2-barrel carburetor had a choke, you may need to add a new choke control mechanism for the 4-barrel carburetor.
Gaskets and Seals: You may require gaskets and seals between the new 4-barrel carburetor, the intake manifold, and any other components you may be replacing.
Fuel Filter: Consider adding a fuel filter to ensure clean fuel flow to the carburetor.
It's important to double-check the specific requirements and parts compatibility for your 350 Chevy engine before making any modifications. Additionally, consider seeking assistance from a qualified mechanic or car enthusiast if you are not familiar with performing these types of modifications on your vehicle.