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Gold Sti Wheels USDM or JDM wanted

I read where someone stated they could maintain 17psi of boost at redline. I have a mbc and according to my logs, this would be very difficult, if not impossible, for me to do. I can raise peak boost but I still drop to about 13psi at redline.

Anyone else have luck doing this? I am not too concerned though since I have a 20g sitting here that I will be installing soon.

Greg
 

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it is very unlikely you could get the factory IHI turbo on the USDM to hold 17 to redline being that it isnt that big... it is possible to do but you need a bigger turbo.
 

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also isnt there a fuel cut of some sort? and if you hold boost that high for that long wouldnt you just REALLY be leaning out a lot, unless set up seperately by an AFC or something?

Robert~
 

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I have my EBC set at 19.5 and only hit fuel cut on long 5th and 6th gear pulls. I have recorded spikes up to 21 with no issues.

I think the turbo holds good boost to redline, but I can't confirm it as the EBC is not mounted where I can monitor it closely while driving. I will have a passenger watch it tonight when I am at the track.
 

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staticx313 said:
also isnt there a fuel cut of some sort? and if you hold boost that high for that long wouldnt you just REALLY be leaning out a lot, unless set up seperately by an AFC or something?

Robert~

Basically it depends on the programming. It would depend if the ECU is in closed loop (listening to the 02 sensor to measure af ratio) or in open loop which uses a pre-programmed map. Where the STi switches between these two modes is beyond me. Perhaps a tuner could chime in - never happens : )


-st
 

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Xman said:
I have my EBC set at 19.5 and only hit fuel cut on long 5th and 6th gear pulls. I have recorded spikes up to 21 with no issues.

I think the turbo holds good boost to redline, but I can't confirm it as the EBC is not mounted where I can monitor it closely while driving. I will have a passenger watch it tonight when I am at the track.
i thought boost cut was 17.2 ~psi? That and I thought the efficiency range was ~18psi for the turbo anyways. Do you really see a benefit of going that high with boost?

Thanks singletrack, that makes sense. I was just wondering as people were worried about simple intakes leaning out the a/f ratio, more of less upping the boost 5+ psi over stock.

Robert~
 
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