A little search found this
'The Forester GT uses a relatively low output version of the EJ20 turbo – it uses an 8.5:1 static compression ratio, a small turbocharger and intercooler, relatively tame camshafts and a conservative ECU tune. Max output is 125kW and there’s 240Nm at just 3200 rpm. A five-speed manual or four-speed auto comes fitted. For the MY01 version output was increased 5kW and 5Nm. This came from altered cylinder head intake ports with Tumble Generator Valves, a larger turbine housing, fitment of a pre-turbo cat converter and updated engine management and ignition systems. '
http://autospeed.co.nz/cms/title_The-Subaru-EJ20-Turbo-Guide/A_2775/article.html
Translation from the Japanese wikipedia
'With first [regashii] EJ20 which debuts after that continues to repeat improvement 1989, as an engine of the new times which change to the EA type which goes back the basic design to the era of Subaru 1000, the leading engine of the Subaru car which even as of 2010 is sold in the country has become.As for the aerodynamic volume displacement as for 2.0L (accurately 1994cc) and head structure adjusting to the model which is loaded, there is a SOHC16 valve and a DOHC16 valve, also the DOHC engine of intercooler attaching turbocharger on-board type for the sport/luxury grade is prepared.You are proud of wide line-up such as thin combustion type (EJ20N), environmental corresponding type of CNG specification (EJ20C) and the LPG corresponding type which is loaded onto for the Hokkaido taxi company to in addition to.'
Looks like its a WRX engine but different add-ons (turbo, cams, etc) if you use it the short block should be a standard open deck and you'd have to add your wrx parts on.