Oil line restrictor size for s14 t28 turbo

[240 Doubledrive]

Hey guys i just put in my s14 t28 turbo into my s13 93' sr20det redtop motor and i got a huge oil leak on the oil feed line to the turbo. The leak is coming from between the motor and the banjo. I have the copper locking washers on both sides but it doesn't seem to help. I talked to some guys at a shop and they said that the s14 t28 needs stronger lines because of stronger pressure. True? I went out and got a stainless steel oil feed line from a DSM that has a -4 opening. Does anyone know what size of restrictor fitting i need to put on the end that is going to the block and what size the opening is on the block? I know it needs a restrictor because I've read about people wearing out their seals in the turbo. Any help would be greatly appreciated. Thanks..