* Engine modifications: Has the engine been modified in any way (camshaft, heads, carburetor)? Modifications significantly affect timing.
* Ignition system: Is it the original points-type ignition or a later electronic ignition system?
* Engine condition: Worn parts can affect optimal timing.
* Fuel type: The type of fuel used can influence timing slightly.
To find the correct timing:
1. Consult your owner's manual: This is the best source for the factory-recommended timing specification *for your specific engine*. It should specify the base timing and possibly any adjustments needed for vacuum advance.
2. Look for a sticker under the hood: Some vehicles have a sticker indicating timing specs.
3. Use a timing light: With a timing light, you can find the actual timing. You'll need to find the timing marks on the harmonic balancer (or damper) and the pointer on the engine block. The owner's manual will show you how to do this and the proper procedure.
Without knowing the specific configuration of your 1968 Dodge 318 truck engine, it's impossible to give you a precise timing value. Attempting to guess the timing could damage your engine. Find your owner's manual or consult a qualified mechanic.
