SO over the weekend me and a mate upgraded the turbo on my RB20 to either an RB25 neo turbo or a VG30 (unsure what i ended up with. says OP6 on the rear housing)
anyway...
we replaced the turbo with the above
the stock front pipe with a 3" one
and the decat with a catco highflow cat.
drives fine, only running R33 waste gate actuator pressure (5.5psi or whatever).
before changing the turbo over i had a decent spool/induction noise.
now it sounds like a stock MK5 golf turbo. very quiet, high pitch whine. so what happened?