* Specific camshaft: The camshaft's specifications (advertised duration, lift, lobe separation angle) will significantly influence the ideal timing. The manufacturer's instructions should be your starting point. Mild street cams often recommend initial timing in the 10-16 degrees BTDC range.
* Fuel type: The octane rating of the fuel you'll be using will affect how much timing you can run without detonation. Lower octane fuel requires less timing.
* Compression ratio: A higher compression ratio necessitates less initial timing to avoid detonation. The .030" overbore increases the compression slightly, but the effect depends on the piston choice.
* Ignition system: The quality and performance of your ignition system will impact how well the engine ignites the air/fuel mixture.
* Exhaust system: Restrictions in the exhaust system can also affect the optimal timing.
How to find the best timing:
1. Consult the camshaft manufacturer's instructions: This is the most important step. The cam manufacturer will provide recommended initial and total timing specifications.
2. Start with the recommended initial timing: Set your distributor to the initial timing suggested by the camshaft manufacturer.
3. Use a timing light: Use a timing light to verify the actual initial timing.
4. Gradually increase total timing: With the engine running, slowly advance the distributor until you hear any signs of detonation (pinging or knocking). Back off the timing slightly once you detect detonation.
5. Monitor engine performance: The optimal timing will deliver smooth running and good power, without pinging.
Caution: Incorrect timing can damage your engine. If you're unsure, consult a professional mechanic experienced with engine tuning. Improper timing can lead to detonation, which can cause significant engine damage. Don't just blindly follow a generic number found online.
