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Rb25Det Not Boosting Well

rb25debt

By rb25debt,
in Engines & Forced Induction

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rb25debt Contributor

rb25debt

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Hi guys, i have a r32 with a rb25det neo in it from a rs4 Stagea. Car was originally auto but is now manual converted.

the problem i have is, it will boost up to around 8 psi and the gate opens. But it doesn't really feel like its boosting. Its also a bit hesitant.

It has a master power t04e, front mount, all the basic mods. Ive only recently got it and have just began tidying it up. I'm pretty sure it hasn't been tuned for the t04e so that could be the problem. But the thing is when it hits boost it almost feels like its letting all the boost out, sort of like a exhaust leak.

Im just learning things atm and trying not to use the turbo in the mean time.

Any ideas?

Thanks for any help guys

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GTSBoy Grand Master

GTSBoy

Posted
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Nonononononojnononopnonononodondonondonooooooo

You can't try to boost up a Neo ECU past about 11 psi on a STANDARD turbo without causing it to clip the air-flow meter, hit the boost limit (there is a boost sensor connected to the crossover pipe) and various other shits and giggles.

If you try to boost it up on a BIG turbo, then expect the shits and giggles to start happening at lower boost. 8 psi would be about right.

The thing will make boost, but the ECU will overfuel and cut timing so badly that it will be slow slow slow. Push it further and they will actuall give you a very nasty hard cut.

If you keep driving it like this you will damage it. You have to either piss that shitful turbo off or do something about the ECU (and the AFM and the injectors and probably the fuel pump).

rb25debt Contributor

rb25debt

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Nonononononojnononopnonononodondonondonooooooo

You can't try to boost up a Neo ECU past about 11 psi on a STANDARD turbo without causing it to clip the air-flow meter, hit the boost limit (there is a boost sensor connected to the crossover pipe) and various other shits and giggles.

If you try to boost it up on a BIG turbo, then expect the shits and giggles to start happening at lower boost. 8 psi would be about right.

The thing will make boost, but the ECU will overfuel and cut timing so badly that it will be slow slow slow. Push it further and they will actuall give you a very nasty hard cut.

If you keep driving it like this you will damage it. You have to either piss that shitful turbo off or do something about the ECU (and the AFM and the injectors and probably the fuel pump).

Ok sweet as man, theres not much that can be done with a neo ecu aye. would my best option just be to put a standard 25det turbo on it? I don't want to make big power, i'd prefer it to be reliable and standard.

GTSBoy Grand Master

GTSBoy

Posted
Posted

Ok sweet as man, theres not much that can be done with a neo ecu aye. would my best option just be to put a standard 25det turbo on it? I don't want to make big power, i'd prefer it to be reliable and standard.

Yes, there is something you can do about the Neo's ECU. It is actually far better than an R33 ECU in that regard. You can get it Nistuned (which is a tunable daughterboard which gets installed inside the ECU) for, well, about $600 I guess. If it then needs to be tuned you pay for dyno tuning too.

You'd actually be well advised NOT to put a std 25 turbo on there. They are all getting a bit old. They are ceramic. They can and will die at random.

I suggest that you do some searching on here amongst the millions and millions of posts about what a good turbo option would be for you. I'm not going to type it all out again.

rb25debt Contributor

rb25debt

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Yes, there is something you can do about the Neo's ECU. It is actually far better than an R33 ECU in that regard. You can get it Nistuned (which is a tunable daughterboard which gets installed inside the ECU) for, well, about $600 I guess. If it then needs to be tuned you pay for dyno tuning too.

You'd actually be well advised NOT to put a std 25 turbo on there. They are all getting a bit old. They are ceramic. They can and will die at random.

I suggest that you do some searching on here amongst the millions and millions of posts about what a good turbo option would be for you. I'm not going to type it all out again.

Cool, cheers for the help man, i appreciate it. I'll look into the Nistune daughterboard as it sounds like the best option for me. I also noticed there was a hole in the hose that comes of the j pipe. Would you know what that part is called as i need a replacement one.

rb25debt Contributor

rb25debt

Posted
  • Author
Posted

If you're in Sydney and want a road tune for your basic mods for your Nistune I have both software, hardware and a portable wideband.

Cheers bro i live in New zealand though, i'm pretty keen on getting a Nistune

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