oil line restrictor for turbo
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TECH Resident
Joined: Aug 2003
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From: orlando, florida
oil line restrictor for turbo can anyone please tell me where to get the restrictor for the oil line on the TT kit and how to install it. i have a newly rebuilt turbo and i`m getting alot of oil into my intake ducting, so I think i need to install the restrictor but i can`t find any info on where to get one. thanks for any help. 
Re: oil line restrictor for turbo Well im trying to find all the part numbers to put a oil resitricter on the turbo.
Here are the ones ive found so far, a few fittings are missing, still hunting them down.
I beleive the turbo takes a 1/4" NPT threard, my oil line is a 4an fitting. it currently has a 4an to 1/4 npt on it (least thats what it looks like, havn't took them off to verify 100%)
NOS makes a 3an to 1/8 npt that takes a jet to the 3an cone, basically your restritor. this is NOS part # 17952. Talking with detriot speedworks they advised me to start with a 52 jet (NOS P# 13750-52)
So i need a 1/8 to 1/4 npt and a 3an female to 4an male
Problem havent found a 3an female to 4an male
they do have a 4an female to 3an male which Jegs sent me incorrectly, when i asked for the other.
If i cant find one, i guess i need a 4an male to male, and a 3an female to female.
NOTE: reading corkey bells maxium boost last week, i found in there a topic on how the turbo needs little oil pressure to survive, It said if the turbo gets more then 60psi of oil pressure the oil will press past the seals even if their good, getting into the system.
I looked at my oil pressure gauge and it reads over 60psi most of the time. problem......yes.
Here are the ones ive found so far, a few fittings are missing, still hunting them down.
I beleive the turbo takes a 1/4" NPT threard, my oil line is a 4an fitting. it currently has a 4an to 1/4 npt on it (least thats what it looks like, havn't took them off to verify 100%)
NOS makes a 3an to 1/8 npt that takes a jet to the 3an cone, basically your restritor. this is NOS part # 17952. Talking with detriot speedworks they advised me to start with a 52 jet (NOS P# 13750-52)
So i need a 1/8 to 1/4 npt and a 3an female to 4an male
Problem havent found a 3an female to 4an male
they do have a 4an female to 3an male which Jegs sent me incorrectly, when i asked for the other.
If i cant find one, i guess i need a 4an male to male, and a 3an female to female.
NOTE: reading corkey bells maxium boost last week, i found in there a topic on how the turbo needs little oil pressure to survive, It said if the turbo gets more then 60psi of oil pressure the oil will press past the seals even if their good, getting into the system.
I looked at my oil pressure gauge and it reads over 60psi most of the time. problem......yes.
Staging Lane
Joined: Nov 2001
Posts: 75
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From: Illinois
Re: oil line restrictor for turbo That makes sense...if you have ever read about those guys that build jet engines out of old turbos...they run very low oil pressure and spin the turbos to extreme speeds. They cant even get them started if the oil pressure is too high. And for them this is like 20psi. They run something in single digit territory when starting them and maybe ramp up to mid teens...And they are spinning them at 120,000 RPM or more. Just something to think about 
I need to get a hold of that book...is that the name of it? "maximum boost"?
I need to get a hold of that book...is that the name of it? "maximum boost"?
Re: oil line restrictor for turbo i just bought a handfull of the aluminum cast pieces that bolt over top of the oil filter and drilled them to different sizes with #'d drill bits. one i had in last was a .042 i think (#42)
Thread Starter
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Joined: Aug 2003
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From: orlando, florida
Re: oil line restrictor for turbo So no one makes the restrictor you have to kinda rig your own. my oil pressure is also always above 60 psi, so now i know why it smokes with the new turbo. thanks for the help guys.
Re: oil line restrictor for turbo 
this is the cast piece with the two 10mm bolts on it.. this on your car stock just sits there and for the turbo kits they have you drill it out to supply oil to the turbo.. instead of putting a restrictor in the line, i just changed the size of the hole i put in the aluminum piece to the size restriction i want. they sell numbered drill bits representing how many thousandths of an inch they are in diameter.. thats what i used.. same sizing as a nitrous jet's units.
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Thread Starter
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From: orlando, florida
Re: oil line restrictor for turbo so what your saying is that you have a .042 hole suppling oil for the turbo, damn is that small! is that enuf oil to keep the turbo lubricated thats only about the diameter of the lead in a #2 pencil. I found two 1/4npt 4an fittings at work exactly like the one thats in the top of the turbo now but the only differance is these don`t have a hole in them so i can drill what ever size hole I want. I think the fittings are off a old R12 freon gauge they were to screw the hoses onto when you weren`t using them.
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Verdad Gallardo Thread Starter
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From: orlando, florida
Re: oil line restrictor for turbo well i drilled a .075" hole through one of the fittings and replaced the original one with it. how do i know if the turbo is getting enough oil? The last thing i want to do is starve the turbo. just for informative purpose the original fitting has a .165" opening so it`s less then half the size now. Thanks.
Re: oil line restrictor for turbo It would be nice to rig up a pressure gauge to see how much pressure the turbo is getting.
but like corkey said "the turbo needs little oil to surive"
best way would be to start big, then work your way down till the smoking stoped.
on my set up i can easily switch out jets to adjust.
those little holes can still flow alot, with 40-60 psi pushing them.
but like corkey said "the turbo needs little oil to surive"
best way would be to start big, then work your way down till the smoking stoped.
on my set up i can easily switch out jets to adjust.
those little holes can still flow alot, with 40-60 psi pushing them.
