No compressor discharge on big 16g

[r6speed]

I currently have a dual manual boost controller from Dejon (the one that has an in cabin switch to go from LO to HI). With the stock turbo I had a vac line coming off of that into the compressor discharge (little nozzle). I just installed the Big 16G turbo and it does not have that little nozzle to hook up the boost controller to. So What do I do with it? I'm very confused now! Any help would be appriciated I was unable to find anything about this in search. Thanks in advance.

 

[pboglio]

There is a screw boss cast into the front of the compressor housing, tap that with 1/8 NPT tap, then pilot drill a small thru hole into the compressor housing. Go to ACE hardware and pickup a 1/8 NPT barbed brass fitting, wrap with teflon on the threads, and your done.

 

[r6speed]

Brand new turbo and I have to tap my own hole in to it? Sounds risky and how stupid is that!? Why don't they come with it? Any way to hook up the boost controller without that? Thanks

 

[pboglio]

Stupid? It doesn't come with it because the stock 1g compressor outlet elbow comes with a welded on barbed fitting. You aren't going to be using that on a 2g, hence you need another boost source.

If the turbo is off the car it is stupid simple to do, stick a rag in the compressor outlet first. I used a .375" dia drill bit, drilled maybe a .375" deep or so, then SLOWLY tapped with a 1/8 NPT tap backing in and out to clear chips, then using the barbed fitting screwed in as a drill guide I drilled a 1/8" thru hole or something like that, pulled the barbed fitting out to clear the chips, then wrapped threads with teflon tape, then put screwed fitting back in.

Or just drill a hole in your outlet j-pipe and tap that for a barbed fitting.

 

[GRAVEDIGGER]

Just run it to one of the manifold ports that are there. You may have one going to the BOV and one going to the FPR and/or boost guage. You can tee in with the FPR, but don't tee in with the BOV.

 

[r6speed]

NEW DISCOVERY:

I found a little part on the compressor housing right before going into the J pipe some female threads....pictures attached...I also found a little bolt that came with the kit that fits in there perfectly like it was meant to be plugged...so I have a few questions now.

1) Is this outlet for a little nozzle?
2) where do I find one of those threaded nozzles? Home Depot?
3) what would happen if I plugged it and plugged the boost controller outlet just to start the car and make sure everything else is holding up?

Thanks in advance again

 

[r6speed]

The boost guage is tapped into the intake manifold...Its a greddy BOV so I have one hose coming off of the intake mani to the top of the BOV one hose from boost controller to wastegate and one from boost controller to BOV adjustment nozzle and one just hanging there now. But I think I might just be able to find a fitting to go into those threads already there and use that as long as it actually goes all the way through (cant really see as you can tell its all ready all put together, which is the reason I don't want to drill anything its finally done...or so I thought)

 

[GRAVEDIGGER]

If the threaded hole goes all the way through to the inside of the compressor cover then yeah, that's your boost source you need. Stick something in there to tell if it goes all the way through. If it does go through then you already know what fits it with the supplied bolt you have. Take it you home depot etc. and match it up with a barbed nipple that will fit the hole and you're good to go.

 

[r6speed]

Now why didn't I think of sticking something in there? Good thinkin I'm on it

 

[->PrOjEcTGS<-]

That threaded hole is for a 10mm bolt to hold the 1g turbo's coolant lines down.

 

[GRAVEDIGGER]

^^^ You're absolutely right. That won't work! It's a blind hole (doesn't go through). On to other options. I say hook it up to the manifold. Just don't tee in with the BOV.

 

[r6speed]

Yup your right...it doesn't go all the way through. I can't beleave that, I still say its stupid it doesn't have a barbed fitting on it. So everyone that gets a 16G has to drill and tap there own hole? How could I tap into the J pipe? Its pretty thin

 

[r6speed]

so your saying tap another hole into the manifold?

EDIT: Just cerious, if I can tap into the intake manifold (say the 90 degree pipe going to the throttle body right where my boost is tapped in) why can't I tee into the line going to the BOV?

 

[GRAVEDIGGER]

You have one hose coming from the manifold to the BOV, that's good. You have one hose from the boost controller to the wastegate, good. You have the other one going from the boost controller to the BOV adjustment nozzle, (not sure how the Greddy works, but that doesn't sound right.) And I'm assuming the one hanging there is the one you are trying to hook up now? If this is correct, just hook up the hose that is hanging there now to the intake manifold on the other port that's already there (going to FPR and tee in if you have to)

 

[->PrOjEcTGS<-]

This is what I did with mine.

Drill a proper sized hole.
Tap it with a 1/8npt tap
Mix up some JB weld
Put JB weld on threads of barbed fitting
Thread in a barbed fitting

Done...

 

[r6speed]

The greddy has a barbed fitting on it just for adjustment coming out the bottom...So the line going to the Fuel pressure regulator is the one I need to tap into? I have never even looked for the FPR but I'm sure I can find it

 

[GRAVEDIGGER]

Yes the fpr is a good boost/vac source to hook the line to. Or you can read this about where and why to hook your BOV and boost controller and such. There are alot of good things here but you have to take the time and read it. http://www.dsmtuners.com/forums/turbo-system-tech/262071-mbc-teed-bov.html?highlight=bov

 

[r6speed]

OK scratch the BOV hooking up to the boost controller I have been told I can just leave that nipple on the BOV disconected its nothing...SO now I have moved so many hoses I don't know what goes where now.

I need one hose to tee into the FPR and one goes to the wastegate...which is which now? Dam I confused the heck out of myself...heres a pic which is which do you know?

 

[r6speed]

Good thread...I will not be teeing into the BOV line

 

[GRAVEDIGGER]

^^^ Ha ha ha You so silly. It looks like the hose where you have your hand on would be the one that would have gone to the compressor cover which now will be going to be teed into the fpr hose. The other hose should go to the wastegate. What is that at the top of the boost controller? Up above your hand. I can't tell, but I think that's where you make your adjustment. Just want to make sure I'm seeing it right.

 

[r6speed]

So I THINK the line I marked in RED goes to the wastegate and the one in WHITE goes to FPR...sound right? look right?

 

[r6speed]

Ok so I was wrong..other way around...and yes that is the adjustment...its basicly a dual stage manual boost controller just so I can run around 10lbs but with a switch in the console go to 14lbs (this way when my girlfriend says "babe can I drive your car to get us food" I can say yes and just switch that switch and she has no idea ha ha)

 

[GRAVEDIGGER]

OH BOY! That's exactly the opposite of how I thought it was. I'm not familiar with the dual stage boost controller.

EDIT: this it the right way for sure:

red = boost source (manifold/fpr hose)
white = wastegate actuator

 

[->PrOjEcTGS<-]

Why are you wanting to get your boost source from the FPR?

The reason everyone doesn't want you to use the BOV is because most MBC's have a vent. The purpose of the vent is so that the wastegate will close when you let off the throttle. Since most are a ball and spring type controller once the boost drops the ball will close and not let pressure to your wastegate out. This in turn holds it open or severely delays it's action if the vent were not there. Therefore, with the vent in the BOV line there is essentially a boost leak in the line at the MBC. That will make the BOV very erratic and unpredictable in operation. Also, same thing goes for the FPR. If you have a vent in the system feeding the FPR you have a boost leak in that line and your FPR will not see as much pressure. Therefore, your fuel pressure will not rise to the proper pressure as it normally would.

It is recommended that you use a dedicated source for the MBC because of the vent built into most of them.

Just some info for you to think about...

 

[pboglio]

Here's the fitting attached on the 16g housing. I've done it both ways both on the housing and j-pipe previously, either way works fine.