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Greddy Profec B Spec 2 On Gtr

joeleo87

By joeleo87,
in Engines & Forced Induction

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joeleo87 Experienced

joeleo87

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:O

nothing worst then being disappointed with a tune/dyno.

does the stk boost gauge read +7? coz thats 14 psi. if you dont have a tune or remap etc you shouldnt be running 14psi, not sure what stk setting is for 260s it wont be 14 psi tho.

BIT SUS Mentor

BIT SUS

Posted
Posted
:O

nothing worst then being disappointed with a tune/dyno.

does the stk boost gauge read +7? coz thats 14 psi. if you dont have a tune or remap etc you shouldnt be running 14psi, not sure what stk setting is for 260s it wont be 14 psi tho.

Stock boost guage reads 7..... i only picked this car up a few weeks ago.... so who knows whats been done to it

Duncan Grand Master

Duncan

Posted
Posted

The standard boost gauge reads in mm/Hg, 7 is around 14psi.

12psi is standard for an rb26 but there is a small restrictor in the line to the standard boost controller. If you remove that it increases the boost to a nice stable 14psi. Nissan were kind enough to mark the location of the restrictor with a yellow band on the vacuum hose - so if you find the yellow band and no restrictor that is why you are running 14psi....

BIT SUS Mentor

BIT SUS

Posted
Posted (edited)
The standard boost gauge reads in mm/Hg, 7 is around 14psi.

12psi is standard for an rb26 but there is a small restrictor in the line to the standard boost controller. If you remove that it increases the boost to a nice stable 14psi. Nissan were kind enough to mark the location of the restrictor with a yellow band on the vacuum hose - so if you find the yellow band and no restrictor that is why you are running 14psi....

ok. so my EBC is plumbed into the FPR, and car is still running stock solenoid and controller etc. So basically its just a digital boost gauge right now...

The peak reading was 18.8PSI... which scares me..... why would it be this high? especially with that restrictor still in place? or boost cut on the computer?

Did Autech remap the ECU to allow more boost?

Do i have a stuck wastegate?

Could first owner in japan have changed the turbos?

What is a safe pressure for a stock RB26? with ceramic turbos?

car goes in for a tune tomorrow morning, so im trying to dig up as much information as i can!

i'm lost well and truly now.

Edited by BIT SUS
BIT SUS Mentor

BIT SUS

Posted
Posted

Think i found why the car is running 18 Psi....

Had a mate look over the car and took him for a spin.

He said its gotta have hi-flowed turbos and maybe hi flowed injectors, cos it goes harder than any stock GTR he's been in.

Ahem.

Does this mean the ECU has some serious tune and the boost restrictor has been removed?

Duncan Grand Master

Duncan

Posted
Posted

umm no not necessarily, its possible just running 19psi instead of 14 makes the difference. If its running that high you should get the turbos checked out, and your tune (probably has a tuned computer of some sort like you said). It wont run 19psi with the standard system, so "something" has been done to it.

Duncan Grand Master

Duncan

Posted
Posted

hi mate I'm not sure, would have to trace all the lines properly...the way I posted above is the way I did it which is similar. You need to keep the lines as short as possible to minimise spiking

BIT SUS Mentor

BIT SUS

Posted
Posted
umm no not necessarily, its possible just running 19psi instead of 14 makes the difference. If its running that high you should get the turbos checked out, and your tune (probably has a tuned computer of some sort like you said). It wont run 19psi with the standard system, so "something" has been done to it.

I just checked out the computer, its stock, not a power FC or anything, so i assume its had some tuning.

Someone said that the stock wastegates only hold 14psi, unless fitted with a stiffer wastegate spring?

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