[TT Stealth81381]

has anyone ever had a problem with this mbc breaking. right now i am trying to figure out why i am only boosting to 7psi. i was just wondering if anyone has this go bad for them. any info would help
thanks

 

[chunsangp]

I have no problem with boostvalve.com mbc.

Check your vacuum hoses.

 

[TT Stealth81381]

yeah so far i have checked everything. everything seems to be good. i just need to check the vacuum operation on the mbc. i mean i could have blown a turbo but am not sure.

 

[chunsangp]

Then check your mbc if the valve opens and close.

Try do the pressure test and see if there are any vacuum leak.

 

[disturbedkorn]

Just blow through the mbc.
If you can blow through it real easy, then you would get about 7 psi.
If it is hard to blow through then it is set for more than stock psi and it is working correctly.
Sometimes you have to take them apart, because the spring can get bent over and caught on something.
Just be careful as the ball bearing will come flying out.

 

[3KDreamer]

Take apart the valve and realign the spring and ball, sometimes it will jam up in there causing it not to work properly.

Good Luck

 

[TT Stealth81381]

thanks for the suggestions guys i am going to try this out tomorrow to see if it works. i hope it does cause i really am starting to get confused on why this is all happening.

 

[John M]

I had this happen with mine. Cleaning it with brake or parts cleaner will fix it for a while.

I eventually switched to a friend's MBC and have had zero problems out of it.

Here's one of his Ebay ads:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1873137317

I can vouch that it works perfectly and you certainly will get what you pay for.

 

[KuJaX]

i have the boostvalve.com MBC. I'm thinking about going with an EBC one of these days!

 

[boostedzx]

Im the guy who owns PRO Boost. John M has one of my boost controllers and has had no problems with it. I have it on my 94 stealth, my 92 300zx tt, and my 1g talon tsi. I have sold almost 500 of these controllers on ebay. I know what your thinking... Ebay, where suckers buy performance parts. Not true at all. Since Im new here, Im offering a few select members a boost controller at less then MY COST. This is a trial deal. I sell you the controller and you have to write a follow up ad and spread the word (If you like it). If 5 people buy one under your referal, I will send you a payment for what you paid, so basically you get the controller for FREE! Retail price is only $19.98 shipped. I offer a 5 year warrenty on my controllers. I accept paypal and money orders. If your interested in buying one, or interested in the "deal", email me at [email protected] or aim me at philip484.

Check it out on ebay. My user name is pjr210. Heres a dutch auction Dutch Boost Controller Auction
The email in my profile is old and not current. I cant change it though. THANKS!

 

[boostedzx]

TTT

 

[Multiades]

I have had some trouble with the boostvalve.com MBC, none of which relates to it being defective. My experience with this MBC used on my Stealth (w/ all my mods below) is that I get unacceptable spiking and boost falloff in the high-end. I think this is common for MBCs, but some work better than others (design-related I assume).

Right now I have the wastegates set to open directly for stage two of the break-in, after which I will step up to the stock solenoid.

I think the unacceptable spiking on my car is largely due to the long routing of wastegate hoses, a necessity on our engines. Perhaps DSMs fare better (very short, direct boost sample to wastegate path). I can't explain why boost would fall off in the high-end, even with modest boost, DR-500s and no intake leaks that I know of.

I will do a comparison between the stock solenoid at stock boost vs. the boostvalve.com MBC at stock boost and check for spike and falloff.

Makes me want a good EBC.

-Chris Wood

 

[TT Stealth81381]

well i finally found out what is wrong with the car. i found that the front wastegate is not holding vacuum. i assume that the spring inside went bad or the diaphram went bad. so looks like i will be getting new turbo's

 

[John M]

The PRO Boost has no spike and no falloff, at least until my stockers max out at 14 psi at redline. There's nothing an EBC is going to do any better than this one does, and it's less than one tenth the cost.

I am of the school "set the boost the highest you want and leave it there". If you don't want high boost, don't go WOT. If you did go WOT, you did it for a reason and it should be all hands on deck when it comes to boost.

That way I get to chuckle when people have "learning" problems with their fancy EBCs. The ball and spring are dumb and don't need to learn anything

 

[EVILTWIN]

Amen.....Almost idiot proof!

 

[Multiades]

well i finally found out what is wrong with the car. i found that the front wastegate is not holding vacuum. i assume that the spring inside went bad or the diaphram went bad. so looks like i will be getting new turbo's

You can buy wastegate actuators separately. I'm not sure what they cost but not nearly as much as a new turbo.

The PRO Boost has no spike and no falloff, at least until my stockers max out at 14 psi at redline. There's nothing an EBC is going to do any better than this one does, and it's less than one tenth the cost.

I am of the school "set the boost the highest you want and leave it there". If you don't want high boost, don't go WOT. If you did go WOT, you did it for a reason and it should be all hands on deck when it comes to boost.

That way I get to chuckle when people have "learning" problems with their fancy EBCs. The ball and spring are dumb and don't need to learn anything

I agree that a simple ball-and-spring valve should take care of it, but the one I was using clearly didn't. I would really prefer to not spend the money on an EBC. EBCs are - I think - slightly more convenient, and the "overtake" boost mode could be useful if you were to use alky or propane and keep one boost level just below the engagement threshold. CART cars use overtake boost to provide maximum acceleration when it is needed for passing, but it is only used sometimes because the engine is not made to be run that hard continuously. It is surprisingly hard to keep boost below a certain point with your foot (I'm finding this out during my break-in), but once again I can see where just one boost level would work out OK.

-Chris Wood