Thanks Eric,
I thought it might be a little tricky controlling detonation with those boost+compression levels.
I’m currently on 9 psi with 8.5:1 and have the max advance held back to 29 degrees (+/-2 degrees flutter) or the detonation creeps in.
The new bottom end I intend building this year will be much the same as the current one but with forged pistons/rods, oil jets squirting from the main bearing caps like the fiat 1.2/1.4 16v engines and trigger wheel/sensor mounts for programmable ignition initially then ultimately FI.
So to keep it simple I think the current compression mark is a safe bet.
Do you have a preferred piston manufacturer?
Ian