Here's what you need to consider:
* Original Engine: Was the 1980 Firebird originally equipped with a small-block Chevy? If so, the process will be significantly easier. If it had a different engine (like a Pontiac V8), you'll face more challenges with engine mounts, potentially the K-member (the front suspension crossmember), and possibly exhaust.
* Transmission: The transmission's compatibility is just as crucial. A TH350, TH400, or 700R4 are common choices that *could* work, but you'll need the correct bellhousing and potentially adaptors to mate it to your specific 350 block. The driveshaft length will also likely need adjusting or replacing.
* Mounts and Brackets: Even if the Firebird had a small-block, you'll need to ensure you have the correct motor mounts for your specific 350 and transmission combination.
* Wiring Harness: You'll likely need to adapt or replace the wiring harness to accommodate the 350's electrical needs.
* Exhaust System: The existing exhaust system will almost certainly need to be modified or replaced.
* Cooling System: The existing cooling system might need upgrades to handle the 350's higher heat output.
In short: It's *possible*, but it's a project that requires mechanical knowledge and potentially significant fabrication and parts sourcing. It's not a simple bolt-in swap. You'll need to research the specifics of your chosen 350 and transmission and compare them to the 1980 Firebird's specifications to assess the feasibility and complexity of the conversion.
