[Raven]

As some of you know i have an rb20 turbo , oem nissan one, i have xs-power oil lines for it. it has not so big hole, maybe 2mm in diameter, i'll be taking the oil feed from the place alpine recommends and on the turbo-side i'll be using a banjo bolt. just to feel safe , i ordered an atpturbo.com oil restrictor which says
Oil inlet restrictor for T series 1/8" NPT. Oil inlet restrictor for all T3, T3/T4, T04, T72 etc. Turbos with built-in oil restrictor (of .060 hole size). Installed at the oil inlet on turbo to reduce max oil pressure going into the turbo to prevent turbo seal damage due to excess pressure. Input is 1/8" NPT male and output is 1/8 NPT female.

i don't know for sure if my has a built-in restrictor or not, i cannot afford to hook up oil pressure sender through the tee and then again drain oil and then again test....
i worry that if i:
-have a restrictor, the turbo will suffer from lack of grease;
-don't have it, the turbogaskets will be blown in a minute or how much time it takes. anyways, there is no normal turboshop to do the rebuild. please advice.

 

[dvanderk]

I have tested the oil pressure on the head a few weeks ago. After the car is fully warmed up the oil pressure in the head is 10lbs while crusing it is between 15-20lbs. Cold start up it is 25lbs. Now, I know if you tap it off the block you will need an oil restrictor if your tubro doesnt already have one (the garret turbo's are an example one ones which do). I think you can use it with out an oil restrictor on the head because the pressure is a lot lower, however I know you want a more sure answer then "think" so ill invite anyone to state there opinions of my claim.

 

[Raven]

yeah, if the turbo breaks down, i won't be glad to know that you understood that your thought wasn't too right. hey. i have another , simplier question. the restrictor can't make bad, right? it just restricts to the normal flow pressure, not less than needed..?

 

[dvanderk]

yeah, if the turbo breaks down, i won't be glad to know that you understood that your thought wasn't too right. hey. i have another , simplier question. the restrictor can't make bad, right? it just restricts to the normal flow pressure, not less than needed..?

Ya its just a very small hole that reduces the pressure. Looking at it, im suprised it even allows oil to flow through it.... you might be able to get braided oil lines that already have a restrictor inside of it, or on the ends.

 

[Raven]

so who else could share his opinion?
who uses restrictors and what turbos? who doesn't use and what pressure is the maximum you could recommend to have

 

[MoogLe]

umm well i'm not sure but i'm still reading through corky bell's maximum boost and here's what it says in the book

Too much oil pressure can create problems with turbos. It is possible to force oil past oil seals that are in perfect condition if oil pressure exceeds 65 to 70 psi at the turbo. If a particulural engine creates more oil pressure than the seals can handle, it may be necessary to install a restrictor or bypass system to reduce pressure at the turbo.
Problems of oil pressure overpowering the seal are evident in a frequent if not quite contant smoking probblem. Anytime oil pressure exceeds the 65-70 psi range and smoking persists, a resitrictor or bypass should be installed prior to any other changes

right under that quote there's a little table that says at Idle, your minimum oil pressure should be 5 psi with a flow of 0.1gall per minute, at maximum load it should be a minimum of 25 psi with a flow of 0.5 gallons per minute.

so if what dvanderk says is true, you'd be ok up untill maximum load, which he might have not measured i donno...


well, that's the best i could contribute here

 

[Raven]

oh i read max.boost but forgot about that. i'll take that into consideration and try to measure it somehow. thanks

as i understand the seal blown isn't deadly for turbo if after the smoke was found, the restrictor was installed instantly? or is it necessary after that to change the seals?

 

[MoogLe]

oh i read max.boost but forgot about that. i'll take that into consideration and try to measure it somehow. thanks

as i understand the seal blown isn't deadly for turbo if after the smoke was found, the restrictor was installed instantly? or is it necessary after that to change the seals?

no clue there