S15 air intake pipe with blocked take off?? why?

[XTension]

Hi,

I´ve noticed something strange in the intake pipe that goes to the Turbo. There´s a small take off blocked by a screw. I´ve taken this pick yesterday. (little blue pipe with screw in pic)
Help me out. What is this for? i guess i should know it, but i can´t really recall from my previous S14, what belongs there. :wack:
how does it affect boost? i´ve never seen it gone up more then 0.5/0.6...

Cheers
XT

 

[JaseYpk]

you're missing a lot there mate. have you got the standard turbo still?
ok heres what mine looks like -

I'm not an expert, but this is what I have on my pretty much standard engine, So if your engine is supposed to be standard, this is what you should have (my power steering bottle may be different to yours)

Hope this helps

 

[XTension]

AH! thanks mate. It really helps alot!

That´s how i recall them. But mine doesn´t have that, it´s missing all those bits.
Car is bone stock, so i really can´t think why that isn´t in place. Ill try to see if it got relocated somewhere in time.

Otherwise if it´s missing, should i try to source one out or a electronic boost controller would do the same/better job?

Cheers
XT

 

[kieran@silverback]

where does that vacum pipe run too? im assumine some form of boost controller?

 

[XTension]

where does that vacum pipe run too?

In stock form i think it going to the actuactor. Mine´s going nowhere, as it´s blocked.

Watching the photos again, i reckon it simply has been removed,not relocated, has i have that wire conector unpluged and tied to the chassis with a zip tie.
Weird as i would tought the boost would go up if only depending on the actuator. I have to check if the actuator has been touched

Thanks
XT

 

[kieran@silverback]

in the top picture, you can see the ribbed intake pipe, the large intercooler pipe, and a braided hose, this looks like its the vacum from the turbo, where does it lead too can you take a picture of where it end up awa from the turbo?

 

[drifter]

What kieran said, there should be a vac hose connected to the acutator on the turbo. Follow this back to find what it connects to. Could be a electric solonoid, or a manual valve, or straight into the intake piping or plenum. If there seems to be no controller, it looks like you may have an upgraded adjustable actuator? What boost is it running?

 

[XTension]

Right Kieran/Drifter, it´s connected to the intake piping. Here´s a picture:

I´m not near the car now (will be at the end of the day) to check for the actuactor. But i reckon it´s running around .5 / .6 tops.

My best guess is that it may be the standard actuactor, thou i can´t really explain why it would run around .6 if it isn´t being controlled by the boost valve...

Cheers
Antonio

 

[kieran@silverback]

you cant see in your first picture if the actuator is standard or not, but you have no form of boost control other than your actuator, it maybe that you have a restrictor placed in the vacum pipe to regulate boost you would be able to feel it if it has, but really you need a boost controller

 

[XTension]

maybe that you have a restrictor placed in the vacum pipe

Like the one that comes standard, on one of those small plastic hoses. I´ll take that vacum pipe out, and peak inside.

Thank you
XT

 

[S15 SILVIA]

Havnt looked at mine, but would it have anything to do with the standard recirc dump valve? They are plumbed back into the intake pipe before the turbo. Won't be any pressure in that pipe, as it is the intake to the turbo.

 

[drifter]

Like the one that comes standard, on one of those small plastic hoses. I´ll take that vacum pipe out, and peak inside.

Thank you
XT

I'd be surprised if there is a restrictor in there, but you never know. If it's a standard actuator, it will be running around 0.7 bar, the standard solenoid ups the boost in higher gears. At least that's how it works in the S14.

As Keiran said though you need to get better boost control. Absolute cheapo would be a manual valve, but I wouldn't go there imo Cheap and reliable electric boost controller would be a Gizzmo. Simple but more cost would be a Greddy Profec B, even more money and complicated would be an Apexi AVC-R

 

[XTension]

Hi mate,

That´s make sense about the .7 bar, thou i would think that running without the solenoid would make some boost peaks or at least to run a little higher. Which it doesn´t, instead, i think it runs below the .7
I´ve tried the AVCR, but i´m really more of a Profec B fan, as i used to run it on my R33. Very easy to set up.

I might give it a try to one of this new Gizzmo, as they seem to be very good too. I´ll see if i can get a good deal on one.

Thanks
XT

 

[drifter]

Hi mate,

That´s make sense about the .7 bar, thou i would think that running without the solenoid would make some boost peaks or at least to run a little higher. Which it doesn´t, instead, i think it runs below the .7
I´ve tried the AVCR, but i´m really more of a Profec B fan, as i used to run it on my R33. Very easy to set up.

I might give it a try to one of this new Gizzmo, as they seem to be very good too. I´ll see if i can get a good deal on one.

Thanks


XT

Without the solenoid the boost will always be lower The solenoid stops the boost getting to the actuator, therefore stopping it opening too early. Your actuator is probably not far out at around 0.6-0.7 bar

 

[meddler]

I was under the impression without the solenoid it uses the spring in the actuator which is set at about 6~7psi.

 

[drifter]

I was under the impression without the solenoid it uses the spring in the actuator which is set at about 6~7psi.

Yeah, sorry I'm being a plank, getting my bar and psi mixed up Actuator is 6-7psi, with the solenoid you get around 10psi on the S14, maybe more on the S15 to get the increase in power

Not used to all this low boost, Ext wastegate set to 1.2bar, Profec set to 1.7 bar is were it's at

 

[XTension]

The solenoid stops the boost getting to the actuator, therefore stopping it opening too early

I see, that makes even more sense. Sorting an electronic boost controller sounds the best option as they all bring they own Solenoid.

Thanks for you help
XT

 

[XTension]

I was under the impression without the solenoid it uses the spring in the actuator which is set at about 6~7psi.

That would be around .5 BAR? that sounds more accurate to what my standard gauge shows. I think it doesn´t get much more the that. In fact i said it runs below .7 but it might well be below .6 and around .5bar

Converting the 0.5bar would give around 7.2 PSI, so i guess thats it.

In the end, i need an electronic boost controller

Cheers
XT

 

[meddler]

actuator spring set to 6~7psi = .41~.48 bar

standard boost setting 8psi = .55 bar

obviously this depends on the gauge and the spring. It may vary slightly.

An EBC is the way to go. Please don't get one of those cheap reed valves off the internet. They are prone to boost spiking, which is not really very good.