Originally Posted by Ænema
In a perfect world(no limit on octane) the higher the compression ratio the more power the engine will make. Period.
However, with pump gas you run into an issue of the high compression ratio making the engine very likely to pre-ignite and detonate. So you take some CR out to make the engine less likely to knock.
Makes sense. The reason I said that was because when going through a lot of different threads on other platforms people tend to run lower compression when making big boost however, when using big turbos, they typically don't build boost until later in the powerband. So with the lower compression ratios, they are losing a lot of their low end - mid range since they are making minimal boost.
Looking at the powerband of the RB turbos, they seem to be a very quick turbo and don't build large amounts of boost so I can definitely see where you are coming from.