Tomorrow i'm taking my car to mitsubishi, to have them check out my tranfer case/ transmission. There is a howling sound that there when the car is driving from time to time and it gets louder when at wide open throttle. Anyways can i disconnect the mbc controller or would that cause hell. I'm going to try to hide it, if i can.

 

DO NOT take the car in with a mbc. They will void warranty asap!!! Take it off, trust me.

 

so how can i take it off. Will it ruin anything. I have a flash by dynoflash and other mods. But the mbc is the only thing im worried about. Do i need to put anything back on?

 

Yes, you need to put it back to stock. If you just remove the boost controller, you will have unlimited boost, at least until your engine explodes. At the very least, connect the pressure outlet from the compressor pipe to the actuator.

 

no, you'll have about 12PSI, what the wastegate is set too.

 

Just reconect the stock hoses back in, simple as that

 

Since the original poster asked this question again in another thread, I will answer this. You are incorrect. If you just disconnect the MBC and have nothing going to the actuator nipple , you will have as much boost as the turbo can produce, assuming the flapper door doesn't get blown completely open by the exhaust gas pressure. You will be limited to 12 psi if you connect a pressure source to the actuator nipple with no boost controller in between, but he didn't ask about reconnecting anything. So I assume he is just talking about just removing, as in, disconnecting the 2 vacuum hoses from it and going about his merry way. Not only will that produce "unlimited boost, but he will also have a big vacuum leak.

So, that's why I suggested (in my first post) for him to run a line the the actuator nipple. If he does that, then yes, he will be limited to whatever the stock actuator is rated at.

 

Nope

I removed mine at the track and hit a MAX of 12PSI, which is what the wastegate is set too.

You'll have as much boost as the wastgate can handle, which is about 12PSI, the MBC simply creates a vaccume untill a certain boost is reached and then opens the Wastegate although the wastgate is already opening as it is just not all the way. Now I DID get a spike of about 15-16PSI but it always falls to about 12PSI from what it is set at the factory. NOW if you tighten your wastgate it'll hold more, if you weld it shut, well then you'll be fully boosting whatever the turbo can do.

BUT simply removing the Boost controller will not make it open boost unless some how you also clog the wastegate nipple with something.

Try it, I am serious it works like this .

 

So couldn't he just remove the MBC, drive it to the dealership without going into boost and then re-install it later?

 

You could remove it but just hook it back up to stock, it's easy.

 

Sorry Matt - 4ce fed is correct. The WG will stay shut unless the exhaust gas forces it open.
You will overboost.
MBCs don't create vacuum, they funnel BOOST pressure to the WG actuator.
You need 12lbs of BOOST to overcome the spring and start to open the WG.

Don't believe it - go out and disconnect the line from your WG and drive around.
It's your turbo...hope you have a boost guage, and quick reflexes.

 

Ok then please tell my car to stop making 12 PSI when I remove my MBC In all honesty how could it? I mean it is only held shut by a spring, that spring is set at 12PSI. by the factory, so as soon as it hits 12PSI it opens .

For a goof I pulled it off at the track expecting what you stated, and open boost situation I had it completely off with NO vaccum tubes, just a naked turbo with nothing but an exhaust manifold. I had some C112 in the car so if I hit like 28PSI (which is what I was hoping for ) I would be ok for that second or two. Anyway I launched REAL hard and spiked to MAYBE 15PSI and then it fell flat to 12PSI and held steady. I ran a 13.6 At 101MPH this with many mods and flashed AND 272's


Read above.

 

The 12 psi to overcome the spring pressure comes from the actuator nipple. If you unplug it, then 0 psi reaches the actuator. The exhaust gasses do not produce 12 psi against the flapper door, if that's what you are thinking. If you unplug yours and it opens at 12 psi on your boost gauge, then it must open alot earlier when any type of boost is applied to the actuator nipple. If it won't boost past 12 psi with nothing connected, then that means that the exhaust is blowing open your flapper door. The exhaust gasses will also blow it open at 12 psi with a boost source connected to the nipple. So you will never be able to boost past 12 psi, regardless of what you try to set the boost to. The exhaust gasses will always overcome the force of the actuator at 12 psi, since nothing that goes into the actuator is there to help hold it closed longer.

The only reason I can see any of this happening is if your BOV and MBC are connected to the same line (going from the MBC to the actuator, which would be stupid). If you disconnect the actuator line and didn't plug it, then the pressure that is also trying to hold the BOV shut will be venting and causing a leak, thus not allowing the BOV to seal. The pressure inside the upper IC pipe could blow the BOV open at 12 psi with nothing on top of the diaphram to help keep it closed. However, the turbo is still creating 'unlimited' boost, it's just being leaked out the BOV. If your gauge is tapped from the intake manifold, you will only read 12 psi, because of the leak.

 

I can hold 21PSI with my boost controller or what ever I have it set too, and 12 with out it. This is my findings

 

Edit: nevermind.