* Engine specifics: A 383 stroker is a modified 350, and the modifications (camshaft, compression ratio, heads, etc.) significantly affect optimal timing. A mild cam will have different timing requirements than an aggressive one. The same is true for compression ratio and head flow.
* Fuel type and quality: The fuel's octane rating impacts how much advance is safe before detonation occurs. Lower octane fuel necessitates less initial timing.
* Ignition system: The type of ignition system (points, electronic, etc.) and its condition influence the accuracy and reliability of the timing.
How to find the correct initial timing:
1. Consult the camshaft specifications: Your camshaft manufacturer's instructions will provide a recommended initial timing range. This is your starting point.
2. Use a timing light: This is crucial. You'll need a timing light, and ideally, a mechanical or dial-back timing gauge for greater precision.
3. Set the engine to Top Dead Center (TDC) on the #1 cylinder: Ensure the engine is at TDC on the compression stroke (both valves closed). This usually involves checking the timing marks on the crankshaft damper (harmonic balancer) and the timing cover.
4. Connect the timing light: Clamp the timing light to the #1 spark plug wire, connect it to a 12V source, and point it at the timing marks.
5. Start the engine and observe the timing mark: The timing light will illuminate the timing marks on the balancer. Note the degree indicated. This is your *initial timing*.
6. Adjust the distributor: Loosen the distributor clamp and rotate the distributor to adjust the initial timing to the manufacturer's recommendation (from your camshaft specs) or slightly lower (e.g., 10-12 degrees BTDC, or Before Top Dead Center – but this is just an example).
7. Fine-tune the timing: Once the initial timing is set, you'll likely need to do a "curve" adjustment with your distributor's mechanical advance or use a programmable ignition system to optimize the timing throughout the RPM range. This usually involves finding the point where your engine runs smoothly and efficiently without detonation (pinging or knocking). This is best done with a vacuum gauge and using a dynamometer (if possible) for precise measurements.
Important Considerations:
* Detonation: Listen carefully for any engine pinging or knocking. This indicates detonation, and you must retard (reduce) your timing.
* Professional help: If you are not experienced working with automotive ignition systems, seek professional assistance. Incorrect timing can damage your engine.
In short, there's no magic number for a 383 stroker's initial timing. You *must* use a timing light and carefully adjust the distributor based on your specific engine setup and the camshaft manufacturer's recommendations.
