The HEI (High Energy Ignition) distributor revolutionized small-block Chevy performance, and its use in a 350 Chevy engine remains a popular choice for enthusiasts seeking improved reliability and power. This guide delves into the intricacies of the HEI distributor for your 350 Chevy, covering everything from its advantages to installation and troubleshooting.
Understanding the HEI Distributor's Advantages
The HEI distributor offers several key advantages over its predecessors, making it a preferred upgrade for many 350 Chevy owners:
- Increased Spark Energy: The HEI system generates a significantly stronger spark, leading to more complete combustion and improved engine performance. This translates to increased horsepower and torque.
- Enhanced Reliability: The electronic ignition system eliminates the points and condenser found in older distributors, which are prone to wear and failure. This results in a more reliable ignition system with less maintenance.
- Improved Starting: The stronger spark provided by the HEI makes starting easier, especially in challenging conditions.
- Easier Installation: Compared to some older systems, the HEI distributor is generally straightforward to install, making it a popular DIY project.
Choosing the Right HEI Distributor for Your 350 Chevy
Selecting the correct HEI distributor is crucial for optimal performance. Several factors must be considered:
- Engine Modifications: The level of modification to your 350 Chevy (e.g., camshaft profile, compression ratio) will influence the optimal HEI distributor curve. A more aggressive cam will require a different curve than a stock cam.
- Vacuum Advance: Some HEI distributors incorporate vacuum advance for improved fuel efficiency and drivability at lower RPMs. Consider whether this feature is desirable for your application.
- Mechanical Advance: The mechanical advance mechanism within the distributor adjusts the timing based on engine speed. Choosing a distributor with a suitable mechanical advance curve is vital for achieving peak performance and preventing detonation.
- Brand Reputation: Opt for reputable brands known for quality and reliability. Research and read reviews before making a purchase.
Installing Your HEI Distributor in a 350 Chevy
Installing an HEI distributor in a 350 Chevy is generally a manageable task for someone with basic mechanical skills. However, precision is crucial. Here's a general overview (always consult your specific distributor's instructions):
- Preparation: Disconnect the battery's negative terminal. Remove the old distributor and any related components.
- Alignment: Carefully align the distributor's rotor with the number one cylinder's position. This is critical for proper engine timing. Consult your engine's manual for the precise procedure.
- Installation: Install the new HEI distributor, ensuring it's securely seated.
- Wiring: Connect the HEI distributor's wiring harness to the appropriate terminals.
- Timing: Set the initial ignition timing using a timing light. This step is crucial for optimal performance and engine health. Incorrect timing can lead to reduced power and potential engine damage.
Troubleshooting Common HEI Distributor Issues
While generally reliable, HEI distributors can occasionally experience problems. Here are some common issues and their possible solutions:
- No Spark: Check the power supply to the HEI distributor, the ignition coil, and all wiring connections. A faulty coil or a broken wire is common culprits.
- Intermittent Spark: This could indicate a failing HEI module or a problem with the distributor cap or rotor.
- Poor Performance: Incorrect timing is a major cause of poor performance. Recheck your timing setting using a timing light.
This guide provides a comprehensive overview of HEI distributors for 350 Chevy engines. Remember to consult your specific distributor's instructions and your vehicle's service manual for detailed guidance. Careful attention to detail during installation and regular maintenance will help ensure years of reliable performance from your upgraded ignition system.
