Minor timing issue becomes a major problem

What kind of timing light do you have?

 

Does it have an advance dial?

 

OK, then making a 30* mark on your balancer will help. Crank the engine, or turn the crank with a breaker bar so that you can see the factory mark on the harmonic balancer. Standing in front of the car and looking down at the mark, measure EXACTLY 1 3/4" CLOCKWISE from the factory mark, and make a second line. Use a different paint color so that you can tell the difference between it and the factory mark. It is VERY IMPORTANT that you be as accurate as possible when you measure, and make the line thin. This corresponds to 30* of crankshaft rotation.

When you run the engine and check the timing with your light, you will see your second mark below the factory mark. As you rev the engine, you will see both marks move up. When all of your mechanical advance is in, the second mark should align with the timing tab. The RPM this occurs at will DEPEND on the springs installed in your distributor. The stock springs will not allow this until 4600 RPM. You do not want to rev your engine that high in Park/Neutral. That is why you need lighter springs so that full mechanical advance occurs at an RPM that is much lower. The yellow springs that come in the Crane adjustable vacuum advance kit are ideal. They let all the advance in by 2000-2500 RPM.

With those yellow springs installed, distributor hold down loosened, and the vacuum advance disconnected and plugged, rev the engine and watch your second mark. Increase the RPM until the second mark will move no higher. With the engine held at that RPM, turn the distributor to align your second mark with a number on the timing tab scale. Your mark equals 30*. If you want 32* total timing, align it with the 2* mark. If you want 34*. align it with the 4* mark. Tighten the distributor hold down and shut the engine down.

After you are done, either reinstall your stock springs, or other springs to allow full advance by 3000 RPM. If you elect to use lighter springs to bring in your advance sooner than stock, it may be necessary to shorten the amount of vacuum advance degrees to 8-10*. I recommend you reinstall the stock springs for now, and hook your vacuum advance to manifold vacuum. You can always swap the springs out, and then modify the vacuum advance if necessary. Keep it simple for now.

 

You don't need a dial back light if you make a 30* mark.

 

Yes, read post #28.