Understanding that tight deck clearances (piston to head) in the 0.040" range are beneficial to controlling flame-front propagation, how much more conservative must one be when tight deck clearances are not attained?
As an example, a Gen 1 chevy small block:
Using a modern aluminum head with a fast burn chamber, tight quench clearance and flat top pistons, running north of 10:1 static is not that risky on 91 octane.
how much more conservative must one be when you can't get that tight quench clearance, and/or resort to domed pistons to get the compression up? understanding that all of these things negatively influence flame-front control.
I'm aware of how cam timing influences static timing, so if one wants to respond in terms of dynamic compression, I'm good with that too as i can easily back my way into a static.
In my mind, with the proper cam timing one should be able to run 10.2:1 on 91 octane if the deck clearances are optimized. but with a larger quench clearance around 0.060", that number should probably be quite a bit lower. my gut says 9.75:1, but it is just a gut feeling and isnt really based on anything other than a basic understanding of the priciples in action.
in the end here, i'm trying to pick a combination of pistons and head chamber volumes to build something that will run decent on 91 octane.