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was it overboosting?

Grey skys

By Grey skys,
in Engines & Forced Induction

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Grey skys Enthusiast

Grey skys

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Went over to my cousins house the othe night for a few drinks and we ended up looking in my engin bay. He noticed that the boost controller was plumbed back on itself. Was my car overboosting, and if so wouldnt the turbo have shit itself from 18 months of overboosting

Cheers Jon

ps can someone tell me how to put photos in I have taken 2 to show what is going on :D

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Roy13 Enthusiast

Roy13

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It sounds like the waste gate is still connected to the plenum line, so in effect the solenoid carn't bleed off any eccess leving u with less boost if anything.

? for u getting a car from WA & want to register it in NSW are your compliance rules the same, do u have a australian compliance plate?

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Grey skys Enthusiast

Grey skys

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When we changed the plumbing the turbo doesnt spool up as much, the car seems to have more grunt and the power comes on much harder and smoother.No I dont have a boost gauge because I thought that I was running stock boost soI didnt feel the need for one. Silly me:)

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Damo Community Regular

Damo

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The way it was set up was ok. The boost solenoid (that was bypassed) allows the boost to jump from 5-7 psi above approx 4800 rpm. If it is set up the way it was u will not have the 2 stage boost. In otherwords u will get 7 psi from as low as 3000rpm. Its up to u how u set it up, I would go back to how it was.

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Roy13 Enthusiast

Roy13

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The way its set up in the before picture is no good as u thought as it will over boost but from memery the size of that tubing will only give u approximatly 14psi thats why it wasn't hitting the boost cut. the after picture is ok but will only give u 7 or 8psi like Damo said. If u ask me ur better off bleeding a bit off to give u 10psi. Won't give u the bottom end punch of 14 but will increase life of engine and turbo and give u almost the same top end if its a pre 95 model.

P.S. my quickest time of 13.8 was done on 10 psi :flamed:

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The Mafia Grand Master

The Mafia

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the series 1 and 2 have boost cut at 12psi and more.

Without that little nissan boost controller colenoid connected you would only be running 5 psi.

The nissan one bleeds of a little, and runs the car at 7 psi after around the 4500rpm mark.

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      By luke gtr · Posted

      Welcome!  If possible,  would live to see some pics. How long was it away getting the work done? Hopefully it feels like a new machine.
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