I have two(2) timing marks on a harmonic balancer for a 327/300 engine.
Anyone have any idea why or have seen this before. Not sure which should be used to set timing.

Thanks!

 

Dunno. That balancer could have been on another engine, with a second mark. Where does the mark(s) set at the timing tab at idle, and how's the engine rpm? Is it hard to (slow) crank, but start? If so, the timing is too far advanced.

 

Set the engine at TDC and whichever mark lines up with 0 on the scale is the one to use.

 

Thanks Old Chevy, TDC with the mark at 0 is what I did and engine runs smooth. Just never ran across this before.
Much thanks!