340 Engine issues

Robin House said
• Initial – 12
• Vacuum- 28
• Mechanical – 30

Those timing figures are AFU

What would be "more reasonable" is

Initial 15
Mechanical advance measured at the crank 20

So 15+20 =

That would give you 35 under power

Then ?? 10-15 vacuum maybe as much as 20

would give you an absolute maximum of 35 +20=55 under light throttle cruise