MBC not working

[DSM BoosT]

ok so I have the NXS motorsports MBC and I hooked it up using the vfaq tutorial for the hallman mbc and I put it in and tried it out just stock not turning up and I lost boost like 1-2 psi then I tried to turn it up and it didnt do anything maybe even lost more boost so I have no idea what the problem is, is it because I used this tutorial or what???

 

[DSM BoosT]

ok so I have the NXS motorsports MBC and I hooked it up using the vfaq tutorial for the hallman mbc and I put it in and tried it out just stock not turning up and I lost boost like 1-2 psi then I tried to turn it up and it didnt do anything maybe even lost more boost so I have no idea what the problem is, is it because I used this tutorial or what???

 

[14spectre88]

try following this guide: Best way to install a MBC

 

[DSM BoosT]

yeah but what about those hose going to the intake area underneath where the MAF is. Like the hose coming from the wastegate and jpipe are already going somewhere, it wont mess it up to take those from where they are going and stick them in the mbc???? im confused

 

[->PrOjEcTGS<-]

On a 2g there is a hose that comes from the turbo's compressor housing. This line then has a T in it and goes from the T to the WGA and from the other nipple on the T goes to the BCS. From the BCS a line goes to the intake to recirculate the bled off air. The stock BCS is a bleeder type boost controller.

You need to remove the line from the turbo and put a longer line in that will go to the bottom of the MBC. Then, out of the side of the MBC goes the line to the WGA. Remove all lines going to and from the BCS and cap off the port on the bottom of the intake.

You lost boost because you are not yet to a setting that will increase pressure. The stock BCS was already increasing boost beyond what the WGA's spring pressure is. Just remember turning the MBC's knob clockwise will increase boost and counter clockwise decreases it. I'm guessing you need to screw the MBC's knob a little bit more before you'll see an increase in boost.

 

[14spectre88]

i think you're talking about the hoses going to and from the stock boost solenoid. Basically what you're doing is bypassing the solenoid (which tries to act as a boost controller). So to answer your question - no it won't hurt anything. Forget that guide on the VFAQ and just follow the one I showed you above to the tee (read it 10x if you have to...it'll make sense when you're done). Also, you can still use the stock hoses, which is what i did...

 

[DSM BoosT]

makes so much sense now haha thank you and thank you for explaining it to me so clearly, I am learning everyday haha thx again

 

[viperlp01]

If you only boosting 1-2 psi then you have other problems.. the wastegate will alway give you "say" atleast 7 psi on a 14b.. SO you have a boost leak or something other going on that might hinder your use of the MBC...

 

[->PrOjEcTGS<-]

If you only boosting 1-2 psi then you have other problems.. the wastegate will alway give you "say" atleast 7 psi on a 14b.. SO you have a boost leak or something other going on that might hinder your use of the MBC...

No, he's saying he lost boost pressure by 1-2psi. So if he was boosting 12psi stock, he's now at about 9-10psi.


OP, Do you have an aftermarket boost gauge? The stock "boost gauge" is not very accurate at all. It only converts what the MAF is seeing for airflow and tries to convert that to boost pressure. If you don't already have a good aftermarket Mechanical boost gauge, then I suggest you get one before turning up the boost any.

 

[djalogik]

is the this a bleeder type boost controller? also take it apart and make sure you are not missing a ball or spring inside.

 

[DSM BoosT]

yeah I have a after market boost gauge, I figured it out, I did this setup ^^^^^ and the intake hose that I put in the mbc (I put it back to normal and going to try the other way out) and the nipple was leaking air thats why I was loosing pressure, everything is ok now Im at like 10-11 psi as before

 

[DSM BoosT]

Ok so I tried both the ways to install a mbc. I tried the tee off the BOV and the hooking up the turbo line and the waste gate actuator and each way I tried it stock boost then turned the knob in and it still read the same thing?????? I checked all the lines and the intake hose where I capped it off.

Could the old BCS have something to do with it?? All the lines that where going to it are not in it and are hooked up to the mbc. so is there something else I need to disconnect on the bcs? I dont know what else it could be help! thanks

 

[DSM_PWR]

Dont tee it off the BOV!

Did you try this
http://www.dsmtuners.com/forums/articles-turbo-system-intercooler/237982-best-way-install-mbc.html

 

[DSM BoosT]

yeah thats the one where you do it from the turbo in the one way and then the other one comes from the waste gate

 

[DSM_PWR]

Possibly have it backwords?

The old BCS wont have anything to do with it, leaving it disconnected is correct...

If you have an air compressor, you can test the MBC/WG by hooking up a line to the turbo side of the MBC and push air through it to make sure the WG is openning up.

If not, then your WG is the problem

 

[DSM BoosT]

fixed it.... I am a retard.... I had the ball on the outside and didnt even think of it......WOW thanks for everything though Im running safely at 14-15psi

 

[Defiant]

Holy shit, start the thread three or four more times and see if that helps.