Forge universal MBC install

[MSPJUANK125]

I just bought a universal forgeMBC and im wondering if there is a certain way to install it it is basically stock i just have a 3" turboback exhaust, FMIC, and an intake. I read that "bleed" type MBC's arent too good but i need to see if it actually can help me out with my lag and flutter. Im running my bov straight to the main vacuum line, my boost gauge and wastegate actuator hose teed off to my intake mani i know that one end goes to the wastegate actuator hose im just wondering where to get my vacuum source for the other side?

 

[jeffmsp]

take the line currently running to the stock wastegate and hook to forge mbc "in" port.

then make a new line and run from forge mbc "out" port to the stock wastegate vac nipple.

if you get it backwards...not good as boost will begin to rise uncontrollably.

make sure your first few runs are only part throttle with the mbc on the lowest setting and if you see boost is rising too high then back off right away and check to make sure its not backwards.

not a bad idea to have 93+ gas in the tank.

even on lowest setting just having it on the line should add ~1psi before you even start adjusting it.

 

[MSPJUANK125]

I only see one line out of my wastegate.. And thats the actuator nipple where is the other one located? Yeah i run 93 octane no matter what but is my set up right? Like the bov to main vac line

 

[jeffmsp]

yes there is only 1 line to wastegate.

just run a vac line from intake manifold to mbc "in".

then run a line from mbc "out" to wastegate.

it cannot be described any easier than this.


intake manifold------->mbc------->wastegate

 

[MSPJUANK125]

Thanks man thats all i needed to know

 

[MSPJUANK125]

I tried it like that and it really didnt do much it just dropped my vacuum from -25 to -20 im still lagging and all i get is flutter is that the only way to connect it? Because ive looked at diagrams and the acuator hose is connected to right to the compressor housing but i dnt see it on my turbo though before all this happened my intake mani was just plugged in to my boost gauge is there anywhere else it could have been plugged to?

 

[jeffmsp]

the vac/boost line from the manifold opens the wastegate at 6-7psi stock. by putting the mbc inline you are disrupting the signal to the wastegate so that it takes more than 6-7psi of boost pressure for it to open.


the reason your instructions show it there is because it is a universal mbc and some cars have the vac/boost line "T fitting" on the turbo outlet. it does not matter, you can source the vac/boost line from anywhere on the charge side (turbo compressor outlet, intercooler piping, intercooler, intake manifold etc)

sourcing it right off the turbo gives the worst spool up, but best most linear boost levels. sourcing from the intercooler is the medium setting, sourcing from the intake manifold gives fastest spool but will cause slight spiking of boost pressure.

either way the difference is so minor you would barely notice it.

if you are losing vac it is because you have done a poor job on your connections.

if you are getting more flutter then your BOV definately has a crappy vac connection.

the boost gauge, BPV and wastegate line all most be top notch vacuum line with really good connections for everything to work right.

Go buy some zipties and make sure everything is tight.

dont **** around with this stuff or you are going to be complaining about how your motor blew up driving down the street. if you dont completely understand what you are doing just put the vacuum lines back to stock and walk away.

 

[jeffmsp]

and btw if your turbo is lagging it has nothing to do with this.

odds are you have another problem (more than likely leaking IC couplings(anything but T-bolt clamps are a joke and should be replaced asap), a bad bov connection or an intake manifold leak).

the stock setup should spool very quickly and if yours doesnt the last thing you want to do is slap a mbc on there. fix the issue dont try to band aid s***.


when is the last time you inspected your 10 year old turbo for shaft play and for any oil in the intake/intercooler piping?

before you went and bought a mbc to crank up the boost.. right?

if your car is running poorly the absolute 110% last thing you ever do is go crank up the boost.

get it running properly without the mbc, then once everything is PERFECT you can start think about upping the boost.


IMO start from your intake, make sure every coupling is tight and PERFECT
next make sure each and every coupling and clamp on the intercooler piping is tight and PERFECT
then inspect your intake manifold and vacuum lines. make sure everything is tight and PERFECT.
keep the MBC off for now. go for a drive. if you are still lagging then you have bigger problems.
if everything seems OK it is time to start thinking about the MBC again.
take some pics and post em up if you are still confused.

you mentioned you have a BOV. did you relocate the MAF? or are you blowing off metered air?

what are you using to tune the car?
without a piggyback or engine management of some sort there really isnt much headroom to up the boost, you will just run into fuel cut once the airflow reported by the MAF is higher than the stock ECU will allow.

 

[MSPJUANK125]

Im not trying to ******* band aid s*** or trying to get my boost up to make it faster i had my clutch replaced and it was working fine before i got cheap labor on my clutch but the guy doesnt know too much about turbos so it was my mistake everything else got plugged in fine its my bov that doesnt vent anymore i looked at past owners of the car and he metioned having a MBC which i never saw at 9 psi and no i dist do any of these upgrades the maf isnt relocated after my bov so yeah i know its running rich i dont know how it was tuned ive had it for a year and it ran perfect until now i know not to **** with s*** trying to blow itvup im not stupid its my daily driver im not interested in building it up just yet until im familiar with everything in it like i said ive only had it for a year ive only done basic upkeep to keep it running fine thats all im not completely fuckinh ignorant so chill.

 

[IshSonP5]

Im not trying to ******* band aid s*** or trying to get my boost up to make it faster i had my clutch replaced and it was working fine before i got cheap labor on my clutch but the guy doesnt know too much about turbos so it was my mistake everything else got plugged in fine its my bov that doesnt vent anymore i looked at past owners of the car and he metioned having a MBC which i never saw at 9 psi and no i dist do any of these upgrades the maf isnt relocated after my bov so yeah i know its running rich i dont know how it was tuned ive had it for a year and it ran perfect until now i know not to **** with s*** trying to blow itvup im not stupid its my daily driver im not interested in building it up just yet until im familiar with everything in it like i said ive only had it for a year ive only done basic upkeep to keep it running fine thats all im not completely fuckinh ignorant so chill.

He is only telling you how it is. And he is right...Don't get upset at it. Also, (if I am understanding this correctly) adding an MBC isn't gonna fix your bov and make it vent. If someone prior had an MBC they were probably running higher boost levels. Check all the connections, as stated above. The BOV might not be hooked up, or it is leaking.

 

[MSPJUANK125]

No i understand what hes sayin im not upset at the truth i got mad cuz he said that i was gonna complain about blowing my car up like i was just trying to up my boost and that i only wanna "band aid" my problem like i like my car running like s*** thats it i only bought it and bought that cheap universal bleed one instead of the ball and spring just to see if they left it out or lost it because it was mentioned i thought that because my boost wasnt high enough i was getting flutter because after the clutch install everything was right exceot the wastegate actuator hose which im still trying to figure out where it was plugged in b4 because it was never plugged in to the intake mani thats all man i wasnt trying to fight with him i respect his knowledge just that he assumed that i bought the MBC to mess around

 

[jeffmsp]

just take a few pics of the vacuum/boost lines on your phone and we can tell you right away if something is hooked up wrong. if the bov flutters more now, odds are the vacuum line is cracked or leaking. everything needs a good vac/boost source or the devices will not work properly. also depending on the brand you may be able to adjust your bov!

here is a pic of my BOV. ideally you want fresh vacuum lines with these metal clamps on all vacuum line connections, though zip ties will also work OK if the connector has a nipple, they just cant be reused.

 

[MSPJUANK125]

Thanks man ill have pics up tmr my bov is a turbo xs type h rfl it might the vacuum lines then its starting to hesitate a lil at idle but yeah i tried adjusting the preload and washers but everywhere i look ppl say they use 3 or 4 washers the guy before me had 8 so idk to me it seems that its on tight but it vented b4 with the 8 i just wanna have my car running fine again thats all thanks for the help

 

[jeffmsp]

one of the biggest improvements you can make to driveability of the car with the venting bov is to relocate you MAF. I used to have a setup like yours for a long time where metered air is vented. after relocating I could not believe i put up with the other setup for so long. i found that i was always running springs too stiff that cause flutter most of the time, or set it for a nice sound but the car would always be stalling out and drove very poorly in comparison to the relocated setup. with relocation you can have the sound and the performance kinda thing.

 

[MSPJUANK125]

Yeah i no the car wasnt perfect before but it pulled i read about how it confuses the ecu and sends the wrong reading of air/fuel making the car run rich i wanna relocate it but idk where to put it ill post the pics tmr so u can tell me what u think

 

[jeffmsp]

sure it is very easy. all you need is 2 silicone couplings and a saw if you already have metal intercooler piping.

 

[jdmkasey]

sure it is very easy. all you need is 2 silicone couplings and a saw if you already have metal intercooler piping.

omg can you please tell me exactly how to do this?
I had a bov on my car for about 3 days and absoutely loved the sound.
but it bogged between shifts and wanted to die.
then i threw a code p0172, bank 1 too rich, so i took it off and it went away.
but i really want my bov back on my car.
i dont have metal piping though :\ is there anyway around not having metal IC piping?
please lmk.

 

[jeffmsp]

just go to google and type "protege+maf+relocation" and then click on "images". It will show you tons of pics from many people who have done it.

unfortunately you will need metal pipes and silicone couplings to get er done, however you only technically need to do the cold pipe. the turbo to intercooler pipe can indeed stay plastic if you like.

this image pretty much sums up where you want to move the maf.

 

[jdmkasey]

thanks alot! are there any adverse effects to this? since the bov will be before the MAF there shouldn't be any problems with running rich or codes right?

 

[jeffmsp]

correct. also not a bad idea to remove and inspect all intake and intercooler piping/clamps while you are at it. proper T-Bolt clamps are the best to use on boosted cars. I have changed every single clamp in my setup to a T-Bolt now and all vacuum lines replaced with proper clamps and zip ties on every connection. it is very reliable.