a few points, just to make you think:

- if you can hear knocking, and your timing isn't too far advanced, and it isn't lean.... logically something in your engine is broken. if something sounds like mechanical clatter, it usually is.

- you have to go REALLY lean or REALLY advanced to actually hear 'heavy knocking'

- if you were actually getting audiable pre-detonation, your spark plugs would be melting, so what do they look like...?

- lots of types of engine noise will set off a knock sensor, too

a few questions,

I have my afr set to around 11.3 to start
and is this on a wideband or just commanded AFR? if wideband, are you sure of accuracy?

I am getting knock at just 18 degrees?
actual timing or commanded? is your base timing set correctly? just 'cause your aldl data says 18 degrees, or your timing table, doesn't mean your physical timing is 18 degrees.