When building up your engine we strongly
recommend that you make a strong, solidly mounted TDC pointer and attach it to the front
engine plate.
While the head is off, the true TDC can be found with a 'dial indicator' (also
referred to as a 'clock gauge') and then a notch can be filed on the front pulley to line
up with the new pointer. A little dab of white paint makes lining them up by eye
easier.
What's the point of all this you may well ask, well the point is that you can now
accurately time the ignition without either having to lay on your back, or use
mirrors!
What you will need though is a timing light with an adjustable dial on the back which
reads off the degrees of advance.
These are the more expensive type so you may want to find someone ("a friend")
with one.
If you make the pointer out of a piece of bar like this, it will
not be likely to be knocked and moved very easily.
Here are the two timing lights we use in our own shop.
Periodically the Snap-On light gets sent back for a calibration check, along with our
torque wrenches.
Here is the dial end of a Snap-On timing light.
With the engine running at an RPM where the mechanical advance is fully advanced, and the
vacuum line to the distributor is disconnected if fitted, this dial is moved until the
pointer and the mark on the pulley damper line up.
The total advance is then read off this dial.
That's it!
But you have to remember that you will want to do this while you are building the engine,
and before the head is bolted on.
