orifice size for the turbo oil supply on 617?
 

ditto title, Im working on turbo oiling for a swap im doing, and somehow I misplaced the turbo oil feed line. Not a big deal, as it was going to be modified anyway, but what I don't know is how big that restrictive hole might be.
Does anyone have the info?

it would be for a turbo from an 83 300D, manufacturer of the turbo itself is too rusty

EDIT- the data im finding says its 2mm, does that sound correct?

2mm sounds about right...

.060" is the general diameter for most turbos...

excellent! thanks

This is what I have in My Notes supposedly from ForceInduction:
Restricted Fitting for the Turbo Charger + 2mm
2mm, as close to the turbo as possible

You might find back-up info on that at superturbodiesel.

Does anyone know the specific reason for the restriction?

On an 1,800 horsepower Toyota 2JZ inline 6 with a 6" Turbo we only ran a .045" restriction...FWIW

2.0mm = .078" more or less.

I would prefer to see .060" in most cases. Larger restrictions can lead to oil migration through the turbo's sealing rings...

This is new to Me. Where I worked We always replaced damaged Stock Parts with other Stock Parts.



Maybe there needs to be some reverse engineering.
What is the actual size of the restriction in the Stock Turbocharger Oil Line and where is it located?


There needs to be a balance. Too much Oil won't drain out of the Bearing Housing fast enough and cause the leaks you spoke of.

While reducing the size of the orifice a little might not harm the Bearing it is the Oil that cools the Bearing Housing.

Not enough Oil might cause coking/Carbon Build-up on the Exhaust side of the Turbo.

I suppose also if the Orifice is too big it could have an effect on the Idle Oil Pressure.

Interesting points you all have brought up, I'm glad you have mentioned them. If the restriction needs to be close to the turbo, that will work well for my purposes. Ill be making an adapter plate to an AN fitting, and my plan was to install a restriction plate between this adapter and the turbo

Place the restriction at the turbo. Keep in mind that .040" to .060" is the standard for most all units. Think...if .040" to .060" works with the heat, load & turbine speed of a 1,000+ horsepower engine at 8,000+ rpm, why wouldn't it work in a 617???

If I knew what size the Stock Orifice was and matched what is stock size is I would have no doubt that; that size would work.

I believe you will find the hole to be around 2.0mm

Thanks.
Is it in the very brazed on Flange that bolts to the Turbo Oil Inlet?

With T-3 turbos, yes, but I have seen the restriction in the turbo housing with KKK units...

so here was my solution, have not yet tested-

a thin steel plate with a 2mm hole, and then a larger 1/2 inch steel plate with a AN fitting to go to my feed setup

http://i1217.photobucket.com/albums/...psb57d067e.jpg
http://i1217.photobucket.com/albums/...psb5446cc1.jpg

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