Where are the timing marks on 1970 454 corvette with AC and PS?

On a 1970 454 Corvette with AC and PS, the timing marks are located on the harmonic balancer (also called the crankshaft damper). There's usually a timing tab on the balancer itself, and you'll need to align this tab with a mark on the timing cover.

Precise location varies slightly depending on the specific engine and its components, but generally:

* Harmonic Balancer: Look for a notch, a pointer, or a stamped mark on the outer edge of the balancer. This is what you'll align.

* Timing Cover: The corresponding timing mark on the timing cover is usually a mark or pointer cast into the cover itself, often near the top, close to the distributor.

Important Considerations:

* Visual Inspection: The marks can be worn or difficult to see. Clean the balancer and timing cover thoroughly before attempting to find the marks. A flashlight will help.

* Manual: A factory service manual for your specific year and engine is invaluable. It will have diagrams showing the exact location and how to properly set the timing.

* Professional Assistance: If you're unsure, it's always best to have a qualified mechanic perform this procedure. Improper timing can damage your engine.

Without a service manual or a very clear photo of your specific engine, pinpointing the exact position is difficult. Always prioritize using a factory service manual for the most accurate information.