Power difference between TL and SV?

[imago]

Where does the power difference between the TL and SV come from? Is it as simple as cams, injection and exhaust?

The reason I'm throwing these questions up is I need a donor bike. The SV would be more suitable in some ways, eg it has RWU forks which I want, and the TL in others. So I'm trying to work out which I'd be able to harvest most parts from in one hit as obviously it's quite pricey buying a whole running bike.