Timing advice

NEVER RELY ON TIMING TAPE OR DAMPER MARKS!!!
At least, not on a stock, unknown damper.
In order to get the proper markings onto the damper, you need to use the dial indicator method, on a KNOWN GOOD damper, to lay out the timing marks on the damper. Even then, with stock dampers, it's only "close", since rubber allows the outer ring to move.

Here is another "ballpark" method of timing an engine, but it seems to work:

Get a diagnostic tach (your timing light should have one), leave the distributor slightly loose, then rev the engine to @ 2,000-2500 RPMs. Listen closely to the exhaust and watch to see if the engine is twitching, or the exhaust is "fluttering".
While at this RPM, adjust the timing until the engine runs smooth, usually you need to back it off (retard it).

What this does is get the timing at or below the point of fuel detonation, though it'll change slightly the next time you add fuel.

I time all of mine with this method and it's never done me wrong.

Also, use the lightest centrifugal advance springs you can, in the distributor.
The sooner you can get all the timing in, up to the fuel's detonation point, is always best for overall performance.

Mark.