Timing - again

[talltom]

     Well it's time for me to challenge  some with more edu than me, but I'm
armed 
now! 
   Awhile back there was a thread about timing with various and asundry theorys
about what exactly takes place in combustion chamber, what preignition is,
detonation
etc. 
  Ed and Todd both described scenarios designed to set timing to avoid
knock. I've 
maintained that some combustion chambers aren't inclined to knock and are
best timed 
by power. My expierience with these(Fiat and some fe series Fords come to mind) 
suggests that power goes down significantly before knock, and frequently is
accompanied by surging. While it doesn't show to a great extent, the latest 
Circle track Magazine has dyno tests on the latest Ford heads that show that
timing
is best at some point well behind the knock point. I manintain that much bigger
differences than show here are available in the real world.(on track) Having
blown
engs using the knock method, it leaves me a little less than impressed.  It
still
seems that the trick is finding the sweet spot, with knock only useful for a
message
telling you which way to go, and that you need to go a ways. 
  Anyhow, do any of you guys that know about combustion chamber design want
to see
if you can agree on why this is?

   No, I'm not going to argue with you, just watch the proceedings.
 

Ps. I got another bosch d brain brain and it works.(I'm back to a v8 now!)
Can anybody tell me the difference between bosch #0 280 002 013(original) and 
the only thing I could get to replace it #0 280 002 005?