[Black 65 GTO]

Joe,

There are many variables involved when dealing with both the total amount and rate of advance.

These variables are:

Cylinder Head Design
Type of piston
Type of fuel used
Air/Fuel Ratio
Weight of Vehicle
Rear Gear Ratio
Converter Stall Speed

So, you can see that one set of numbers would not work for any combination.

You can either find the total amount of timing that is ideal by running timing loops on either a dyno or at the drag strip. This involves starting at low, say 30 degrees total timing, and increasing advance by two degrees unitil you reach a maximum power (dyno) or MPH at the dragstrip.

Your timing curve involves much more tuning. This will depend on a lot of the examples above as well as if you intend to drive the car mostly on the street. Also include the vacuum advance as part of your distributor tuning. This makes a world of difference in the drivability!

If you are not willing to invest the amount of time required to acheive the best curve (this can take many hours), I would suggest that you send your distributor to a reputable person to have the curve modified to your intended use and car.

As a matter of fact, there are a few guys on this board that specialize in this service.

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