As Jack said I too am running 10.58:1 with zero decked KB107's in a 360 with magnum heads and an XE268H cam. The cranking pressure in my engine is 195 to 205 psi. I have almost 50k miles on the engine running 89 octane with no issues. I have tried 87 but high loads at low rpm do cause some detonation so I stick to 89.
The efficient port and chamber design of the magnum heads do not require as much timing. I have found I get the best performance with 33 degrees of total timing. The XE268H cam likes a lot of initial timing and I am running 17. I have springs in the distributor that have the timing all in at 1500 rpm.
I also run vacuum advance and have it adjusted to add 17 degrees at 14" Hg which happens at cruise in the 40 mph range.
All in all I think my 360 is dialed in pretty well for a street car, I get 16.5-18 mpg around town and 21-22 mpg at 70 mph on the hiway. I have an A833OD with 3.55 gears in a 68 Barracuda.