i was running the fittings i got with my oil lines 4mm restrictor and turbo started to leak through the oil seal but not out the exhaust but between the 2 housings..........had it rebuilt under warranty and explained to me, that due to the high oil pressure in honda engines, it makes it too high for the turbo charges, i was advised to run a 40thou (i been told that is 1mm) restrictor, but im gonna try using a 1.5-1.6mm restrictor to start with.

good luck....