Well, just for kicks
heres what the
EA 3.2 predicts for a
318 v8 9.83 cr static
ignition timing maximum setting
before (barely audible) pinging first starts
on 87 octane

at Seattle Washington
16 feet above sea level
29.93 inches Hg barometer
92 degrees
65 degrees dew point humidity

RPM......Ignition timing
3200.......22 @
3400.....,,25 @
3600.......27 @
3800.......29 @
4000.......30

@ sign after ignition timing
means the timing has been retarded
from what would make the best torque
to prevent pinging.

In above table at
4000 rpm is where
"mean best torque" timing (mbt)
can first be used
with no retard