milling heads for comp ratio increase

The KB silvolite site has a CR calculator online, as well as other sites where you enter all the specs to find out a gasket bore’s influence on CR.

Compression builds torque which means low rpm power.
The fact it hardly shows up at dynographs is because dyno’s start measuring at 2-3000 rpm, while rpm range of most regular part-throttle driving is in the 600 to 2500 rpm range.

When you start out with a low ‘smogger’ cr ratio, I would say try to get the cr up to ‘modern’ levels.
Especially if the local fuel type allows it.