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Stock Car Running 1 Bar Boost?

hop1308

By hop1308,
in Engines & Forced Induction

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hop1308

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I looked into it as much as i could, and took a few more photos. I found a two prong hose sort of thing that looks like it used to be on the solenoid? just a guess though. and i can see its been attached to another hose thats attached to itself maybe? and then that hose attaches to the golden looking round thing, i got that in a photo too.

Hope these photos explain whats going on a little more

post-78310-0-79711600-1347684029_thumb.jpg

post-78310-0-72636100-1347683759_thumb.jpgpost-78310-0-71394500-1347683767_thumb.jpgpost-78310-0-84699200-1347683775_thumb.jpgpost-78310-0-98690200-1347683780_thumb.jpgpost-78310-0-59937600-1347683791_thumb.jpg

Edited by hop1308
GTSBoy Grand Master

GTSBoy

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Right, so in your first image with the red circles, the circled item on the right I think is your boost solenoid. We saw that in one of your earlier photos. It's not connected to anything, so we can forget about that.

The leftmost circled item in that photo is essentially a T piece (it looks like an F, but works like a T!!). The bottom is connected to the wastegate actuator (the cad plated can at the front of the turbo) and that is where your middle circle is.

So the top two connections from the "T" used to go somewhere useful. One leg would have gone to the boost solenoid, and the other would have had to pick up a boost signal, possibly from the compressor housing, possibly from the compressor outlet pipe.

If you look at the photos that show the "T" you will also see a fourth hose that passes into the same sheath heading towards the back of the engine and going down towards the front of the turbo. I would lay odd on that hase being connected to a hose barb on the compressor housing. Not all R34 turbos have a connection there though. if you look at the photo in this for sale thread http://www.skylinesaustralia.com/forums/topic/409257-std-r34-neo-turbo-like-new/ you will see the spot where a fitting would be drilled and tapped into the front of the housing, but there is none there. My R34 turbo however, does have a fitting on the turbo.

Anyway, what you need to do is find where all of those hoses that I've just talked about go, what they are connected to, draw a map on paper and take a photo of it.

What should happen, if the stock solenoid is not being used and no other boost controller is being used, is that the hose that is connected to the wastegate actuator should just connect effectively direct to the boost source, with no leaks anywhere. The fact that you have 14+psi tells us that there could well be another boost controller hiding in there somewhere (a simple bost T or other bleeder) or that some idiot has just bodged together the hoses and left a leak.

14 psi will destroy your turbo. 14 psi is too much boost for a factory computer and it will rich and retard like fuel was only 20c/litre. You need to work out what is going on and fix it. If this is all too hard, take it to someone. Anyone who knows turbos will be able to work out what is going on in about 5 minutes.

cheers

hop1308 Collaborator

hop1308

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lol this'll make my head explode, i reckon i wont be able to do it right after looking at how tightly packed everything is today. do you know about how much someone that'll look at it for me would charge? and hopefully anyone good in sydney (blacktown area) that knows this sorta stuff?

maybe i should stop flat footing it until then lol

rgb Enthusiast

rgb

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It's hard to get the full story of what's happening here. I did notice in picture #3 & 4 that we don't really see what's happening with the recirc valve. The recirc is the matte aluminium can that has the blue hose on it. It should have a vacuum hose on it as part of the boost control system.

Also, take off the useless snorkel you have there (large black plastic bit in pic 4), and remove the NEO cover plate and post another picture of the recirc valve. What we need to know is where the two hoses from the actuator (brass tin can) are going, so include photos of those two hoses.

FYI I have the stock boost gauge, and a GFB manual boost controller. With the boost set to 10psi, the boost gauge is 9/10 up to the +1 mark.

If you want to limp your car into the CBD area, me and a mate can take a look at it. PM.

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