hey guys got a question maybe someone can help me out with an answer or maybe someone has experienced this.

OK i just installed my new Grimmspeed MBC the other day. Installed everything right exactly the way the web instrictions said. This is not my first mbc install either btw they are pretty straight forward to use.

Anyways i cant get my car to hold more than 20lbs boost and that is just untill the wg is opening. I have a forge wastegate with the 19-24psi spring installed.

i previously has a ****ty mbc installed on the car and i was able to make 25psi with it

Just wondering if anyone has any info on the issue, i even tried switching the hoses around and with the mbc adjusted max both ways i cant hold anymore boost than what the wg is allowing before it opens on spring pressure.
thanks all..

 

Maybe a silly response but u sure all the hoses are good? No leaks? I had a similar issue and had a small leak in my vac hose

 

Sounds like a spring issue. Maybe the spring in the grimmspeed is a lighter spring and only maxes out at 20 lbs.

 

nope hoses are brand new im sure but ill have to check that

and the grimmspeed mbc is supposedly a top unit compared to the hallmann pro and the buschur mbc's, should be able to use it up to 60psi

i kno its something stupid ill figure it out

 

I don't know much about it and that was just a guess. After looking at it sounds like maybe its an adjustment issue or some thing silly as you said.

 

Does it hold boost at 20lbs?

 

Lines on the boost controller on backwards?

 

Never hurts to perform a boost leak test, a visual inspection will not tell you what you need to know.

 

I thought that too but the car wouldn't reach 20 psi if they were it would just leak and leak and leak.

 

alright guys no offence these are somewhat gradeschool assumptions. did a boost leak check a couple months back hols 27psi in the system no leaks.

the forge wg has a 19-24psi spring in it and its opening right at 20lbs.

the lines on the mbc dont matter forwards or backwords the adjustment goes up or down lol and i tried both ways all the way out and all the way in with hoses the right way and switched around.\

i have ruled out all the basic stuff it has to be a cus hose or something somewhere where my mbc is loosing its pressure.

ill get it al worked out it just confuses me because the other day i was making 25psi with a really cheap mbc now i got a decent one and installed it and i got probs lol its def gotta be a leak between the compressor and the mbc or the mbc and the wg

thanks for all the input and sry for the sarcasm ,p

 

The lines do matter sorry to say. It is a ball and spring unit. I am sure you will figure it out.

 

So, you mention that you switched to a Forge WGA. What I want to know is whether when the car was boosting where you wanted it to did you already have the Forge WGA installed or did you install the Forge WGA later, at the same time that you installed the Grimspeed MBC.

Or, to put it more concisely did it boost to 25 PSI with the Forge actuator installed and only after installing just the Grimspeed the boost dropped down to 20 PSI? Did you install both the Grimspeed and the Forge WGA at the same time?

 

Did you try switching back to your previous crappy old MBC to see if that fixes the problem?

 

You mention that your flapper valve is opening at 20 PSI. Just how exactly are you determining the opening point of the WG?

 

Good point Sparky, your thinking that the wga was changed. Would be a good idea to make sure that is the problem. Take the mbc completely out of the mix and hook the line off the wga to your boost source and find out where it is actually opening. That maybe the problem not enough preload on the wga. This theory makes since, the wga opens up a little to early theres your 5 lbs