15-09-2014, 01:33 PM
(14-09-2014, 08:16 AM)Piggy Wrote:(14-09-2014, 07:04 AM)Poodle Wrote: So the oil pressure is fine..? 4bar at idle still seems a hell of a lot, garrett specify their turbos don't like more than 5bar feed pressure.
60psi actually....but only for ball bearing turbos.
Journal bearings, like the GTB2056vlkr has, use a hydrodynamic film of oil to space them properly, much like crank bearings for instance.
There is the possibility of too much pressure still but it needs to be like 10bar+
Remember it's a VLK, not VLKR - VLKR would be a ball bearing turbo.
These engines have a 5bar pressure regulator for when cold - so I seriously doubt there'll ever be any pressure problems in the turbo... Ball bearing units do need a restrictor, the journal units like these will have the restrictor also as they don't use the oil and bypass a large quantity for cooling like the oil/air cooled jounal bearing units.
This is a water cooled, journal bearing turbo... So uses less oil than a plain oil/air cooled journal bearing unit, but still less than a ball bearing unit. Don't think you can get a pure oil/air cooled ball bearing unit for that reason.
V = Variable Nozzle (VNT)
L = Liquid (Water) cooled CHRA
K = Electronic Actuator
R = Ball Bearing
S = Single Bypass Wastegate
N = Ported Shroud Compressor Cover
NOTE: Doesn't always conform, my old GT2052V was technically a GT2052SV as it had a slightly different compressor wheel...