I will now join the ranks of idiots who do not safety wire
#101
Boost Czar
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Originally Posted by Garretttttttt
Ball Bearing Turbo
Ball Bearing Turbo An oil restrictor is recommended for optimal performance with ball bearing turbochargers. Oil pressure of 40 - 45 psi at maximum engine speed is recommended to prevent damage to the turbocharger’s internals. In order to achieve this pressure, a restrictor with a 0.040' orifice will normally suffice, but you should always verify the oil pressure entering the turbo after the restrictor in insure that the components are functioning properly.
Recommended oil feed is -3AN or -4AN line or hose/tubing with a similar ID. As always, use an oil filter that meets or exceeds the OEM specifications.
Ball Bearing Turbo An oil restrictor is recommended for optimal performance with ball bearing turbochargers. Oil pressure of 40 - 45 psi at maximum engine speed is recommended to prevent damage to the turbocharger’s internals. In order to achieve this pressure, a restrictor with a 0.040' orifice will normally suffice, but you should always verify the oil pressure entering the turbo after the restrictor in insure that the components are functioning properly.
Recommended oil feed is -3AN or -4AN line or hose/tubing with a similar ID. As always, use an oil filter that meets or exceeds the OEM specifications.
#102
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You want that restrictor, over oiling a bb turbo will kill it. It has much tighter clearances, and does not use oil flow to cool the center section as much as the water does. This is somewhat in converse to a journal turbo where it needs higher flow to maintain an oil film and oil is used to cool everything.
I found that over-oiling will turn ball bearings from a rolling element bearing to a sliding element (ala journal bearing)...which is bad. If the ball bearings stop "rolling" between their two contact surfaces you're in trouble. The low contact area makes a very poor journal bearing, and they start to wear quickly...regardless of abundant oil supply. It's really a matter of surface pressure really...same forces as in a journal bearing...but much smaller area. Follow the Garrett advice Braineack posted and you should be fine.
Journal bearings on the other hand have a minimum pressure which is significant...and luckily often pretty low by design. Once you achieve this minimum pressure there are no other concerns with regard to the bearings. The only reason to put a restrictor in a journal bearing turbo is to prevent blowing oil out of the seals.
#108
Former Vendor
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I've been running .035 restrictors for 30k miles on two (three?) different BB turbos. I've never seen a single drop of oil in my charge pipes.
Trey, it might be that heat shield that's getting the EWG hot. I wouldn't worry about it.
Trey, it might be that heat shield that's getting the EWG hot. I wouldn't worry about it.
#110
Tour de Franzia
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I just shipped everything out so hopefully I'll have this car back on the street next weekend...there went my brake money.
#113
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You won't "kill" a Garrett bb turbo by delivering high oil pressure to it. What this will do is force oil past the seals, which will then find a new home in your IC pipes and/or make for a smokey exhaust.
Once you fit a proper oil inlet restrictor, the smoke gradually goes away, the valdez in the plumbing clears up and all is well.
Oh, also, high oil pressure can nullify a bb's low-friction-ness by introducing a bunch of windage. But you won't hurt the bearing. Oil pressure that's too low, sure, that'll kill it.
Once you fit a proper oil inlet restrictor, the smoke gradually goes away, the valdez in the plumbing clears up and all is well.
Oh, also, high oil pressure can nullify a bb's low-friction-ness by introducing a bunch of windage. But you won't hurt the bearing. Oil pressure that's too low, sure, that'll kill it.
#119
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hustler, I may have missed it but if you not seeing signs of oil getting past the turbo's seals then you're fine with the restrictor size you have.
EDIT: just saw that it smokes on startup. Hmm. I don't know if this is related to the turbo--oil pressure on a cold start isn't that high (relatively speaking) and cold oil is viscous and has a harder time working past the turbine seal.
EDIT: just saw that it smokes on startup. Hmm. I don't know if this is related to the turbo--oil pressure on a cold start isn't that high (relatively speaking) and cold oil is viscous and has a harder time working past the turbine seal.