Solenoid - Wiring

[Miltuun]

Helloo!

So I bought myself a Stagea RSFour Series 1.

I'm having some concerns though. The guy of whom I bought it from seems to have disconnected the solenoid alltogether. Which leads to unlimited boost and fuel cut. He probably did it when he installed a FMIC.

But I have no idea where I should connect the two inlet/outlet pipes on the solenoid since there's no sign of any hoses.

Crappy pic attached

Please guys, I would really appreciate some help, and some pics if possible.

And also, total newbie question. I have a button on the dash which is 4 wheels and a "s" inbetween them, like a diff. What does this button even do?

Cheers!

Edited January 14, 2013 by Miltuun

[Brick]

Not sure on the solenoid but the 's ' button is snow mode and locksall wheels in permanent 4wd. Plus I believe it makes it only take off in second gear to stop wheel spin

[KiwiRS4T]

The button on the dash will lock in 50/50 split on the awd from take off. Once you get up to speed the attessa computer takes over again and directs just 5% to the front wheels unless the rears lose traction.

It is common to bypass the solenoid to increase boost but ripping out all the hoses is not the way to go. There should be at least a hose coming from a boost source (usually the pipe leading from the turbo to the intercooler) and going to the waste gate actuator on the turbo often with an adjustable T (or a fixed venturi T) that bleeds boost pressure off to the bov return pipe (can be hard to see). To return to standard you need the boost line going to the solenoid and from the solenoid to the w/g actuator with the bleed line going to the bov return pipe.[ You can tell which ports to use on the solenoid by using a pipe to blow through it with the engine off. Put the boost line on the one you are blowing through and the one where the air comes out goes to the w/g actuator. The other port is the bleed to the bov return pipe.]

Hmm just realised its a while since I saw a stock solenoid so the last three sentences (now struck out) could be wrong. If the solenoid has only 2 ports then the boost source goes to the top port and the bottom port goes to a fixed T going left to the bov return pipe and right to the w/g actuator. There is a restrictor in there somewhere can't remember just where.

I don't have a pic of the stock set up and my car is not stock so I can't take a pic but below is the bypass set up. On the left you can see the boost source on the intercooler pipe. It leads to a plain T which branches left (the bleed to the bov return pipe which is not visible) and right to the w/g actuator.

Are you able to phone the guy you bought it from and ask him? It is unlikely he was running it with unlimited boost.

[scotty nm35]

You can see the white band on that vac hose, that's where the restrictor is. Without it you will run unlimited boost and boost spike in the midrange.

[Miltuun]

Hey guys!

It seems something is very wrong, It makes no sense the way it's wired now.

I actually talked to the guy, he had no idea, he seems to have no clue about anything.

This vacuumhose goes from the wastegate actuator.. Like the image below..

To..

Can anyone make sense of this? Can't fint a restrictor anywhere.. Could someone please share a image of their wiring. Would be mostly appreciated.

Cheers!

[Duncan]

OK, so the hose from the fuel pressure regulator is plumbed to the wastegate? Seems pretty dangerous to your engine's health. The FPR hose is a good place for a boost gauge but not a boost controller......

Basically the wastegate will open whenever there is more pressure than it's spring is rated for. I think the stagea/gtst spring is about 3psi. So as soon as you get 3psi in that hose the wastegate should open loosing all boost.

What you need instead is a small nipple on the intercooler piping somewhere before the throttle...the closer to the wastegate the better as the length of the hoses leads to boost spikes. Take off an intake pipe near the wastegate and have a nipple welded on for a vacuum hose (I've also seen it done by tapping a threaded fitting onto the intake but that may not be reliable over the years). Then connect that pressure source to a bleed valve (eg http://www.turbosmart.com.au/wp-content/uploads/2011/11/Product_bt.jpg) and then to the wastegate. That will let you choose anywhere from 3 to about 20psi reliably, with a standard turbo you should keep it to 10-12psi

[wolverine]

Dunc, I think it is plumbed into the plenum pre BOV from what I can see. It doesn't look like the FPR from the tiny image I am looking at.

[Duncan]

ahh I agree....it looks like it is plumbed into the BOV's pressure source, not the FPR....but that is still after the throttle body and therefore incorrect I think.

Might be time to give the keys and your wallet to a mechanic

[Miltuun]

Thanks guys, I'll have a look after work.

The pics should be clickable for a bigger picture.

[zoomzoom]

What are your goals for the amount of boost you want to run? The setup in KiwiRST's photo is the simplest and safest, but it also has more turbo lag, in both the responsiveness of the turbo and also the amount of boost that can be made at lower rpm.

[Miltuun]

My goals are probably around 0.8 bar (11psi) which seems to be a resonably safe pressure.

I will probably go with duncans setup and order a bleed valve, and also weld a nipple on the piping from the turbo. I got myself a wideband lambda today so that will go in this weekend aswell.

Or do you guys have any other ideas on how I should sort this out? Since I don't have the restrictor which goes in the hose..

[KiwiRS4T]

http://www.ebay.com.au/itm/Turbotech-manual-turbo-boost-controller-THE-ORIGINAL-/220798194994?pt=AU_Car_Parts_Accessories&hash=item3368991532

[Miltuun]

http://www.ebay.com....=item3368991532

Thanks Kiwi, but I'll order something from Sweden since it takes years for it to arrive to Sweden ;-)

You will probably hear from me again with more stupid questions.

Cheers!