Hi Guys,
I'm having issues increasing the boost so i took off my Forge Manual boost controller and was trying to understand how it works.

this one has 2 ports as shown in attached pic (i've the same forge MBC) so when i blew air into port one port it was going being passed thru a very small hole and when i blew air into the other port it wasnt going in. No matter how i turn the knob to PLUS or MINUS.

is this normal behaviour?

 

There is a ball and spring inside

 

Boost goes into one end(2) and there is a spring and a ball in there. The more + it is set at the more the spring compresses making it harder for the air to get passed, raising the boost level. Air goes through it and it practically tricks your waste gate to open at more boost then the spring in the waste gate is for.

 

^ i know this but the behavior i've mentioned in my post is it normal?

 

hey guy you may find that you actually have an internal problem with your mbc.. its pretty straight forward how they work but sometimes they ave defects. I actually juust had the same problem. I boght a GrimmSpeed mbc and i couldnt get it tohold boost. i took it off and tested the ports and no matter which way ya blew or sucked air threw the ports it wouldnt restrict any air at all. i could adjust it all the way from min and max and it would still not restrict air. so i ruled it out to b the mbc itself thats the cause. I hav a 2 year warranty on the thing so i just sent it in t be replaced. This ounds like your issue. I think your mbc is having the same problem mine was. if you have a warranty on the forge stuff id send it in to be replaced

 

Air shouldn't need to go backwards from 1-2. sounds normal. The ball is supposed to block the aird from going through. So yes it sounds normal.

 

your mbc is working normal. the hole is there to relieve pressure going backwards through the mbc

blowing in the correct hole seemingly did nothing because you can't generate more than ~5lbs (not enough to open the mbc) with your body, so the ball and spring will remain closed

 

I see this next thread being " I blew my motor"

 

I second that

 

No! Hopefully not!
I haven't used a mbc before so wanted to know how they work.

 

lol

 

Ignore the haters. Your question was a valid one. Keep asking questions, and you'll be fine.

If you have any additional questions about MBC's or how they work... feel free to post up, or PM me.

 

2 is in, 1 is out to wastegate. blowing through 2 is normal to release air through the bleed hole damper

 

theres a gypsy inside of the MBC, she uses the tears of orphans and black magic to raise and lower boost.... i thought everyone knew this

 

OP: It would be extremely helpful if you could you be more specific. Could you describe in detail the exact issues that you are encountering when attempting to adjust the boost level on your turbo?

Also, it might be helpful if you would post up your complete modification list(i.e. what turbo/cat vs. no-cat/ induction kit/BOV, etc.). Finally, some engine bay pictures of your MBC installation showing boost/vacuum hose routing and connections would be a help in trying to understand and troubleshoot the problem.