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RB25DET high boost issues

Tomak

By Tomak,
in Engines & Forced Induction

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Tomak Collaborator

Tomak

Posted
Posted

Hi guys,

I have this problem in my new setup like turbo overboosting but its not overboosting...its just cutting my turbo off for some reasons at high and low rpms at different boost at heavy load. Like its living its own life. One night i dont have issues and can go for 1 hour without problems accelerate all the time on different gears at heavy load about 1.6 bar and after 1 hour of drving the turbo cuts again. Like i dont have a fck clue what it can be....

How is this possible that car accelerates one time clean and other time turbo is failing, like the boost is unstable or something, ??

I put new GTX3071 gen2 two weeks ago because i thought my turbo failured but the new one has the same issues. It only goes clean every time at low boosts from 1 to 1.3bars. When i hit 1.5-1.7 it feels like overboosting at some point. So i have changed the turbo already.

On my manual turbo display i have overboosting set up limits  to 2.0 bars, i run external westgate precision turbo 45mm with 1.0 bar spring. My turbo housing is 0.83 A/R v band and 6boost exhaust manifold. Rb25det engine IS OEM did not any mods to it.

 

 

 

 

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https://www.sau.com.au/forums/topic/482180-rb25det-high-boost-issues/
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GTSBoy Grand Master

GTSBoy

Posted
Posted

There's a difference between

  • A turbo genuinely not having proper boost control and overboosting,
  • A turbo making boost on one run and not making boost on another,
  • The ECU or a sensor cracking the shits and not working consistently.

Work out whichever it is, then start fixing that.

Tomak Collaborator

Tomak

Posted
  • Author
Posted

I am using actually LINKG4 but never tried to do any temp corrections by myself and i have hard time reaching my tuner right now. He quit his job. Actually i am in position where i can try to fix it myself or need to pay another tuner for complete mapping from scratch again.

I just went for a run on cold and it was smooth ride for 15 minutes on full loads at 1.7 bar so i guess all is ok with my car just overheating issues at some point.?? Maybe this is because of stronger turbo and i never do any temp corrections before. I had before gtx3071 gen 1 with max hp 550hp and did not have this issues. The problem start to occur more often on gtx3071r gen 2 max 650hp. I mean this gen 2 turbo feels much stronger even when i go only on 1 bar from spring, it has way more potential and its more aggressive.

What corrections should i do in the Link G4 ECU? I need some instructions which parameters to change. Is the log necessary for this operation or not? I need to drive around 1h to get this log saved if this helps with anything. Is this engine temp overheating limiter?

 

Murray_Calavera Mentor

Murray_Calavera

Posted
Posted

Based on how random this has been for you, it sounds like it could be fuel surge. 

By any chance has this been happening when your at low fuel levels, and/or accelerating hard round corners or up hills? 

Getting fuel surge will feel like your hitting a rev limiter or boost cut etc. 

 

  • Like 1
robbo_rb180 Grand Master

robbo_rb180

Posted
Posted
1 hour ago, Tomak said:

I am using actually LINKG4 but never tried to do any temp corrections by myself and i have hard time reaching my tuner right now. He quit his job. Actually i am in position where i can try to fix it myself or need to pay another tuner for complete mapping from scratch again.

I just went for a run on cold and it was smooth ride for 15 minutes on full loads at 1.7 bar so i guess all is ok with my car just overheating issues at some point.?? Maybe this is because of stronger turbo and i never do any temp corrections before. I had before gtx3071 gen 1 with max hp 550hp and did not have this issues. The problem start to occur more often on gtx3071r gen 2 max 650hp. I mean this gen 2 turbo feels much stronger even when i go only on 1 bar from spring, it has way more potential and its more aggressive.

What corrections should i do in the Link G4 ECU? I need some instructions which parameters to change. Is the log necessary for this operation or not? I need to drive around 1h to get this log saved if this helps with anything. Is this engine temp overheating limiter?

 

PM me the tune file and a pc log (all channels logged) of it doing it. 

 

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