[olddog]

Phill,

The reason you found it *severely* advanced, is because there is no vacuum advance. The factory spec may have been 8* but the vacuum would pull in another 18-20*.

If you set the initial down to 8* the only time that it will not be severely retarded is when it is at WOT. So people set the initial timing high, for a half ass compromise.

If all the engine is used for is racing, eliminating the vacuum advance is smart. One less variable to tune and fail. You never run at light throttle. You don't care about fuel mileage or emissions.

If you drive it on the road, with one exception, it is stupid to eliminate the vacuum advance. Without a computer, as in EFI, about the only way to get the right timing under most operating conditions is vacuum advance coupled with mechanical. The one exception is if the cam shaft is so radical that you just don't have enough vacuum to make it worth your while. In which case, you have an engine that really shouldn't be on the road.

Put a vacuum advance distributor in it and let someone who knows what they are doing tune or advise you. At least that is one opinion.

Others will argue and tell you what they are doing. You can get by with the compromise approach without vacuum advance. You will be wasting fuel at light loads and running hotter than needed. Ovoid WOT at low rpm, as you will have too much timing and could damage your engine.

PS
You need to know what your vacuum is at idle and buy the correct range vacuum canister. The vacuum must be pulled in solid at idle or the idle will hunt all over the place, because the timing and vacuum will be jerking each other off in a tail spin. Again this needs to be done correctly.