I only have experience with gasoline. As others have mentioned static compression is basically a rule of thumb type figure as it doesn't take into consideration the valve events occurring while your engine is actually running. With a small block ford stroker engine, I have ran 200psi of cylinder pressure with aluminum heads on 91 octane gas without detonation. My dynamic compression ratio was 8.4:1 and my quench was dialed in at .035".
On an iron headed motor with 91-93 octane, I'd keep my dynamic compression under 8.0 (on Pat's calculator) and with Aluminum heads, under 8.5. Quench is super important too, .030-.045" and keep an eye on piston to valve clearance as well.
If you're building the engine and you have access to all the figures and measurements, I'd use a dynamic compression calculator. Personally, I use Pat Kelley's which can be downloaded for free. You have to know how to use the calculator, as the information must be entered in a particular order, but it's a great tool.
You should read his webpage on the topic and download the calculator:
http://members.uia.net/pkelley2/DynamicCR.htmlDM me if you need help with the calculator.
-Dan
