Need specs -- Chevy inline 6 distributor mechanical advance

Does anyone know the MECHANICAL advance curve for the Chevy distributor in a '68 292? I'm setting this engine up for track racing and will be removing the vacuum advance, so what I'm after is the total amount of advance the weights will get me. Also, what's available for springs for that distributor?

 

Three places you might look: try the stovebolt.com web site for all things inline
also inliners international web site, last, look for the book Chevrolet Inline Six-Cylinder Power Manual by Leo Santucci. You can find it at Californiabills.com automotive handbooks 888 511 1530.

 

Is it running? If so put a timing tape on the ballancer and read with a timing light.

 

Not running. On the stand being finished.

It would be great to find a local shop with a Sun tester. Nobody seems to have distributor testing machines anymore. The used ones on Ebay are way too expensive for the infrequent use I'd give it.