Why It's Not a Simple Swap:
* Computer Integration: Modern 350 Chevy engines rely heavily on the computer (ECM) for timing, spark control, and other functions. The distributor is just one part of a complex system.
* Electronic Ignition: The distributor itself is often an electronic unit, with a magnetic pickup for the ignition signal. A non-computer controlled distributor would likely use points and a mechanical advance mechanism.
* Wiring and Sensors: The engine's wiring harness, sensors (like the crankshaft position sensor, oxygen sensor, etc.), and the ECM itself are all designed for computer control.
What You'd Need to Do:
1. Identify the ECM: First, you need to determine if your 350 Chevy has a computer control system (ECM or PCM) at all. Look for a black box near the engine compartment.
2. Determine the Distributor Type: If your engine has a computer-controlled distributor, it's unlikely you can directly swap it for a non-computer controlled one. You'll need to completely modify the ignition system.
3. Replace the Distributor: You'll need a mechanical distributor with points and a mechanical advance mechanism, along with a compatible ignition coil.
4. Modify the Wiring: This is where it gets tricky. You'll need to rewire the entire ignition system, eliminating all the computer-related wiring and sensors. This could involve:
* Removing the ECM: You'll need to bypass the ECM entirely, and potentially even remove it.
* Replacing Sensors: Many sensors used for computer control (crankshaft position, oxygen, etc.) will be useless.
* New Ignition Coil: You'll likely need a new ignition coil designed for a points-based system.
5. Install the New Distributor: Install the new distributor, ensuring proper timing.
6. Tuning: You'll need to tune the ignition timing and carburetion to ensure proper operation.
Considerations:
* Expertise: This process is complex and requires significant mechanical knowledge and experience.
* Cost: Replacing the distributor and rewiring is expensive. You might consider the cost of a new, non-computer controlled engine for a simpler solution.
* Performance: You may experience a performance drop and a loss of efficiency compared to a computer-controlled system.
* Emissions: This conversion would likely fail emissions testing in most areas.
Recommendation:
Unless you have a very specific reason for going back to a non-computer controlled system, it's generally not recommended. The benefits of a computer-controlled system (better fuel economy, emissions control, and performance) outweigh the complexity of converting to a mechanical system.
Instead of replacing the distributor, consider:
* Rebuilding the Current Distributor: If your current distributor is failing, you might be able to have it rebuilt with a new mechanical advance mechanism and points.
* Upgrade the Ignition System: Consider upgrading to a more modern electronic ignition system, which can provide better performance and reliability without going back to a mechanical system.
Before attempting any of these modifications, consult a qualified mechanic for professional guidance and ensure you're comfortable with the complexity of the project.
