Depends what you want to do with it....
Basic bolt ons and you are 200rwhp if you just want a fun streetbike. A piston kit and you are 1441cc good for around 230rwhp+ with a good head cam setup.
As far as slapping on a TURBO they won't hold as much boost stock motor because of the higher compression. However, with a spacer plate and other goodies, they make more power and IMO are all around better. Mods recommended: ferrara valves (though you could use stock gen 1's for cheaper used), 65# Springs, .080 base spacer, head gasket, lower end gasket kit, APE Promod studs / nuts, ape cam sprockets (only 1 is really needed, you could sell the extra).
Also with the dual injector setup and ECU tuning no need for an FMU just a 1:1 regulator. 18psi Greg's bike made 356hp/217tq stock pistons/rods on pump gas...