Are you trying to tune this motor for a car or motorhome? If for a car with stock distributor set the total mechanical timing at or above 4500 RPM in nuetral, make sure and disconnect the vacume advance hose to the distributor when setting the total timing. I like and use the initial timing to be set at or near 14 BTDC to 18 BTDC idling in nuetral below 1000 RPM That usually requires shortening up the mechanical advance slots in the distributor by welding them up and changing the length of them to be able to get 34 to 38 degrees total timing
IHTHs