When Chrysler designed an engine for street towing with 87 octane fuel, they chose 8.4 static compression for the 1995 8L V10.
When Ford/Toyota designed an economy engine for 87 octane they gave the 2008 Ford Escape I4 a 11.7 to one static compression.
Obviously there is a wide range depending on the camshaft and combustion chamber and other factors.
The attached file is a graph from Japanese research showing how coolant temperature, ignition timing, and static compression ratio affect power and fuel economy:
