Hi new to forum did a quick search **** findex owt so thort I'd ask. I recently had my 2008 wrx hatch remapped and the mapper told me he cudnt get the turbo to boost he sed he wanted 1.7 but only got 1.2 so not as much power as I wud av liked he told me it's cos it's on fully synthetic n I shud use semi synthetic oil seems strange to me tho any ideas? Also car has turbo back exhaust n piper cross panel filter