I guess the initial setting depends on how much mechanical advance Langdon puts in his distributor. I've heard look for a total mechanical and initial to be in the 34 degree range if you have a dial back. Remember to DC the vacuum advance when you check for full timing say at 3500 or so. BTW, too much initial timing will cause the starter to drag on warm start ups, it is all a juggling act and with today's alky fuels make sure you jet up the main jet a size or so especially if you drive at sea level and high barometers. 10 % alcohol in the fuel will make you about 5% leaner than otherwise non alky fuels in my book.
Steve
1953 Chevrolet 3100261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY GalleryVideo of the 261 running1964 GMC 1000305 Big Block V6, sm420, the next cab off restoration
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