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Rb20 < Rb25 Turbo Upgrade

Leeroy94

By Leeroy94,
in Engines & Forced Induction

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Leeroy94 Enthusiast

Leeroy94

Posted
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I'll consult a tuner before the install to look at my fuel pressures etc.

Is this nipple on the IC piping going to the intake plenum? I have a strange thing poking out of the piping already that almost looks like a spark plug. My original thoughts were that it was just screwed in to seal up the screw hole that's there so maybe this is the nipple that your talking about?

GTSBoy Grand Master

GTSBoy

Posted
Posted

Is this nipple on the IC piping going to the intake plenum? I have a strange thing poking out of the piping already that almost looks like a spark plug. My original thoughts were that it was just screwed in to seal up the screw hole that's there so maybe this is the nipple that your talking about?

No. On RB20 turbo it is a small brass hose barb coming off a boss on the front of the compressor housing. The boss is there on RB25 turbos, but it is not drilled and the barb is obviously not there. On RB25s they fitted the tapping onto the intercooler pipe. It won't be on your pipework as standard. If you have something it will be because someone added, perhaps for a different boost controller iinstallation.

The hose is only 6mm, or possibly even 4mm ID. The hose (stock) goes direct from the hose barb to the wastegate actuator. If a boost controller is installed then it goes via the boost controller before heading to the actuator.

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Even_Flow Enthusiast

Even_Flow

Posted
Posted

Also I have been told to install that nipple closest to the turbo as possible(or there abouts) for an accurate WG actuator reaction. So in between the turbo outlet and intercooler or 'the hot pipes'

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Joshbigt62r Proficient

Joshbigt62r

Posted
Posted

My opinion is you should really get a tune done if you plan to run more boost than say 10 psi on the 25 turbo on a rb20. Im not up to date with pricing on Nistune boards but is the $990 you stated earlier on the Nistune board installed + tuned? Im guessing it is.???

my suggestion to you is try and find some 444cc standard GTR injectors which come up in the F/S section all the time. Im pretty sure there a direct bolt in, although you may also need the GTR resistor pack. Another member can confirm??? Get the nistune installed and tuned and enjoy. Getting it tuned will make a reasonable difference to power/torque/drivabilitly/engine longertivity and overall better fuel consumption as has been stated.

I could say more but out of time have to go back to work.

Josh

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Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

I remember a forum member name CEFF13 or something similar had pre-made safe tunes (pretty rich and ignition wasn't too advance) for RB20DET with usual bolt ons and a RB25DET turbo for like $150 delivered, including the IC socket etc...

All you needed to do was desolder your old chip and pop in the new one.

I used one back in the days and managed 180 ish kWs at a dyno day.

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Leeroy94 Enthusiast

Leeroy94

Posted
  • Author
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yeah okay.. I guess the only thing I can do right now is install the 25 turbo..

Next track night (yes its a track car) is next friday on the 22nd. So I might attempt the installation the following week.

Ill post results of installation.

Even_Flow Enthusiast

Even_Flow

Posted
Posted (edited)

I also found out yesterday that my 20 turbo elbow doesn't fit my 25 turbo.... Swear I read somewhere they were the same size??? I found the 20 elbow was marginally smaller....

Edited by Even_Flow

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