You see that big thing that looks like a hair drier on this engine..... THAT is the replacement for displacement.... when you build a turbo engine.... you funnel everything into the turbo.... every mod is what's better for the turbo.....

Increasing your compression ratio makes more power, yet you decrease your compression ratio so you can use more turbo.........

same concept with the sr20 vs ka24...... the sr20 is an engine stable at high rpm that has a valvetrain capable of eating more turbo. That is why it's better.