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niran

By niran,
in Engines & Forced Induction

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niran Proficient

niran

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hey every

i have got an rb25 conversion done into my r32 gts-t, as most off you who own a r33 with a rb25 would know that there is a nipple on the pipe that comes off the BOV, when i read through some topics i saw that when using the stock solenoid you have a top and bottom inlet/outlet.. the top goes into the actuator side off the turbo and the bottom has a split where one goes to a vac line and the other goes to that nipple.. is this right ?

however when i try this method my turbo does not go to 5psi (under 4500rpm) and then gradually goes to 7-8psi (above 4500rpm) instead it straight away goes to 1 bar plus(connected an aftermarket boost gauge to make sure as stock one reads only up to 7psi), straight away i backed off the throttle and drove it back home.

so at the moment i have taken another boost source and just run in with a T piece straight to the actuator off the turbo when this is done it runs at 5 psi, which is fine..

does this mean that the nipple that is on the pipe that's from bov has been blocked off?

also something that i quiet cant understand is, if i remove the vac line that is connected to the T peice the car should drop idles or try stall is this correct? however its not, i can hear and feel the air coming through that vac line and i can also even rev the car without affecting idle or engine revs.

does any one know what could be the issue?

thanks, Ni

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JonnoHR31 Grand Master

JonnoHR31

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not sure how the stock solenoid works but a small vac line leak usually wont create too many dramas with idle, probs find the idle valve will flow a touch less to compensate and it'll be a touch leaner than normal.

btw, stock boost gauges are in x100 mm/hg not psi. +7 is close to 1bar

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Ruff Ryda Contributor

Ruff Ryda

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Check it again against vac diagrams man.

Are you sure the turbo actuator or wastegate isn't jamming up in any way? The standard Garrett ones aren't great. Go for HKS or something. Also make sure the EBC solenoid is setup correctly with both vac lines, if it isn't then you will have vac and readings with all sorts of problems.

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niran Proficient

niran

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not sure how the stock solenoid works but a small vac line leak usually wont create too many dramas with idle, probs find the idle valve will flow a touch less to compensate and it'll be a touch leaner than normal.

btw, stock boost gauges are in x100 mm/hg not psi. +7 is close to 1bar

oh ? ok so if im getting around +5 what does that come to? does that mean its running 7-8psi ??

Check it again against vac diagrams man.

Are you sure the turbo actuator or wastegate isn't jamming up in any way? The standard Garrett ones aren't great. Go for HKS or something. Also make sure the EBC solenoid is setup correctly with both vac lines, if it isn't then you will have vac and readings with all sorts of problems.

hey man, nah its not because then if i ran it straight it wouldnt change anything. yep i tried both ways just to make sure swapped the pipes over no difference

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Ruff Ryda Contributor

Ruff Ryda

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Posted (edited)

Yeah, just wondering if the boost controller isn't functioning properly and it's not in synch with the acutator. I would see if another boost controller could fix the problem or another BOV (try BOV first). Are you able able to get your hands on another one to test? If so give it a try.

Edited by Ruff Ryda
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