View Full Version : garret gt turbo`s.......did you or not??

idiot goes sideways
09-14-2006, 06:34 AM
there should be some guys out there with garrett gt series turbos on their sr, ca ,ka ,rb..... like the gt28r gt28rs gt2871....

i have just one question,

did you anything to the oil-feed line like a oil reducer/restrictor to your turbo????

or leafe it stock and drive with full (normal engine) oil pressure?


oh by the way, i know this was asked to death, but somehow i didn`t get it until know....

how much boost can a gt28r running safe?

09-14-2006, 07:33 AM
if im not mistaken they already have the restrictor in it, but it wouldnt gurt to have one on the line just in case also

09-14-2006, 10:47 AM
how much boost can a gt28r running safe?

it dosnt have so much to do with the pressure than the amount of power your motor will be putting out with that turbo. A general rule of thumb here on the online community is 300WHP for stock head gasket is still safe. Going over 350WHP, you should start looking into a metal head gasket.

09-14-2006, 04:21 PM
^^That is debatable, but i think we can all agree that a metal HG is a cheap, safe precaution.

To anwser your question more specifically, I believe this turbo's efficiency range to be somewhere between 12-16psi. However, there is a guy on 240sxforums who ran 19 psi on his gt28, but he was getting ready to upgrade to something bigger, so it wasn't really an issue if it blew. Also, his HP numbers started dropping after 5.5k if i remember correctly, but he had massive amounts of torque.


idiot goes sideways
09-15-2006, 03:52 AM
first thanks for your answers,

a metal hg is no problem..... actualy i must smile a little :)
(this CA18det will be happen a MHG, arp studs,forged pistons/con-rods,fine balanced and weight shaped crank, lighten flywheell, cams......................)
i was told that the engine should be able to running safe 1,8 - 1,9 bar ~25psi+
so this turbo shouldn`t kill this engine (lets hope)

okay, its a s15 turbo (hey it was cheap and should be much better than my old t25)
so there should be a oil reducer already in the turbo....right?

where can i find those oil reducer for the oil line?? never saw one

12 - 16 psi ........should be max 1.1 bar, okay sounds realistic should go with that


09-15-2006, 05:50 AM
Oh, didn't know yours was the s15 version.. keep in mind that the other guy's t28 was a s14 model, and AFAIK the s15 one is more effecient and is capable of slightly more power because it has a bigger AR. Some guys even push these turbos to around 300hp with supporting mods of course.


idiot goes sideways
09-15-2006, 09:54 AM
yes its a s15 tubo

but i THINK there at least two types of s15 turbo

standart s15

and ............. how does it be called ..????... i think it was called s15 r-spec or spc-r ............ anyway something like these wich is slightly different

i`m not too sure how correct it was, what i wrote about the s15 turbo, but something is different

anyway its a simple CHEAP standart s15 turbo, but the max. boost should be the same, or not ? and does it definitely a oil reducer in the turbo?


09-15-2006, 10:01 AM
the one u want has the built in divider.

as far as the oil line, run a banjo style instead of an AN fitting and you will be good.

tErbo b00st
09-16-2006, 12:32 AM
If it is an S15 turbo you WILL need an oil restrictor. The OEM turbo lines contain the restrictor on SRs and CAs. So while the stock oil line has a restrictor in it it is much bigger as it is made for a journal bearing T25, not a ballbearing turbo which requires much less oil. If you run the stock lines you will most likely run into problems as oil leaks past the seals.

Many of the newer GT turbos have built in restrictors, BTW. But none of the OEM nissan turbos.

As far as how much boost to run. If you are on the stock 370cc injectors do not exceed 12 PSI. 10 is safe and just about as fast as a T25 @ 14psi.
If you upgrade injectors the turbo is safe to run to 18-20 psi, but that is pushing it. It is effiecent right around 15 psi.

idiot goes sideways
09-16-2006, 03:12 PM
thanks, thats what i wanted to know

1.buy a oil restrictor
2.dont run above 15 psi (534cc injectors)