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Discussion Starter #1
Turbo XS bleed-type MBC installed, but....

Just installed my friend's turbo xs bleed-type mbc today. Install was easy. Boost is set to 15psi. One thing I don't like about it....Is the way boost drops after 5500 rpm on up. Is it the bleeder type mbc causing this 3-4psi drop till redline? I know alot of you guys are getting the boost drop too, but some of yall are only dropping 1 psi or none at all till redline. What's the fix?

I have a couple ideas on trying to fix it, but I need to see what you guys migh have did. I'm not a fan of bleeder-type mbcs. Ball type(joe p) seem to be much better type. I will probably try to t off a spot on the bov line instead of using that fitting that is on the turbo next to the actuator. This should speed up spool time a little bit. It works best on DSMs, so it should work great on scoobies. That boost drop truly sux!!! Ideas on how to fix will be appreciated. Thanks guys.
 

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Just fixed this problem by getting rid of the bleeder type MBC and replacing it with a Joe P(ball/spring type) MBC. Only drops 1 psi above 5500 rpm. Acts much better and the car pulls much better all the way to redline.

Anyone want to buy a Turbo XS MBC (bleed-type)?
 

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Installed My TurboXS MBC today!

Today some of the Bay Area IClub members had a installfest at their house. I bought a used TurboXS MBC off some dude for $40 and went their and installed it. The first time I had it on, I took the car out, and I could only get 0.5 hkpa. Even turing out the adjusting screw like 5 times. I went back to the install fest, actually took out the instructions, which I really hate to do, and I had the hoses installed wrong. So I put them in the right places, turned in the adjusting screw all the way IN and went adjusting.

It took me about 6 times to get it right. I set it at 1.07 hkpa (15.5psi) And now, HOLY $HIT!!!!! This car Haul$ A$$!!! Its like a whole other car. I can't believe such a cheap part can do so much!!! WOW!!! Best bang for the buck. I think everyone should try a MBC. I love the feel of getting pushed into your seat even harder because of this mod. Forget about a BOV, go for MBC.

Kurlee Daddee
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Re: Installed My TurboXS MBC today!

A BOV will do nothing for performance. Anyone who thinks they do are really kidding themselves IMHO.

With the MY02 you even risk running rich and losing performance.



KurleeDaddeeWRX said:
Today some of the Bay Area IClub members had a installfest at their house. I bought a used TurboXS MBC off some dude for $40 and went their and installed it. The first time I had it on, I took the car out, and I could only get 0.5 hkpa. Even turing out the adjusting screw like 5 times. I went back to the install fest, actually took out the instructions, which I really hate to do, and I had the hoses installed wrong. So I put them in the right places, turned in the adjusting screw all the way and went adjusting.

It took me about 6 times to get it right. I set it at 1.07 hkpa (15.5psi) And now, HOLY $HIT!!!!! This car Haul$ A$$!!! Its like a whole other car. I can't believe such a cheap part can do so much!!! WOW!!! Best bang for the buck. I think everyone should try a MBC. I love the feel of getting pushed into your seat even harder because of this mod. Forget about a BOV, go for MBC.

Kurlee Daddee
(THE ORIGINAL)
 

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kurlee

isnt it amazing the difference of getting full, or close to full boost in 1st and 2nd!!!

i used to run the MBC at 1.07 Bar also, but if you can afford it install the SBC-ID...there is no fall off in boost at all

if you cant do that , at least get the uppipe and then the downpipe and youll really be rippin
 

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Godspeed Uppipe in the mail on its way to me. Can't wait for that!!! And when I get the rest of my money from Subaru, I will be getting the TurboXS Stage 2. Man it is soooo fun playing with this car.

Anyone think with my mods: Samco Intercooler hoses, Resonator removed, WRXfx intake and ITG filter, TurboXS MBC set at 15.5 psi, and soon to come UPPIPE: Should my car run in the mid to low 13's? With a good driver?:D Just want to know. I just am still trippin that a MBC makes your car sooooo fast.

Peace,
Kurlee Daddee
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KurleeDaddeeWRX said:
Godspeed Uppipe in the mail on its way to me. Can't wait for that!!! And when I get the rest of my money from Subaru, I will be getting the TurboXS Stage 2. Man it is soooo fun playing with this car.

Anyone think with my mods: Samco Intercooler hoses, Resonator removed, WRXfx intake and ITG filter, TurboXS MBC set at 15.5 psi, and soon to come UPPIPE: Should my car run in the mid to low 13's? With a good driver?:D Just want to know. I just am still trippin that a MBC makes your car sooooo fast.

Peace,
Kurlee Daddee
(THE ORIGINAL)
Sounds like you've got close to Jim's (PlatinumWRX) mods and he's running mid 13s, so I'm pretty sure you could hit low 13s with the uppipe :)
 

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Turbo XS MBC Flutter?

First of all, I think I have the worst luck here with WRX parts. First my BOV didn't work the way I wanted it. Now my damn MBC that I have had installed for the last month started to flutter. Anyone else have this problem?

It just started happening yesterday, and it only seems to happen at WOT. It will wind the turbo up, and then about half way through the power band it flutters, or spikes the boost up and down. I got pissed off, so I took it off and went back to the stock setup. I also drove the car without the MBC at WOT and there is absolutely no flutter now. So it has to be the MBC. I think I read that Turbo XS MBC's have had this problem. DO you think it is possible to take it apart and fiddle with it?

I really want to put it back on my car. Without the MBC, my car feels like it has half the power it used to. I really would like to get an MBC or some kind of boost controller that is RELIABLE. I would like to check out the Blitz SBC-ID as well. Anyone please comment.

Kurlee Daddee
(THE ORIGINAL)

ps:
On my way back from my test run with my stock setup, I saw a motorcyclist on a Sports bike, he was coming the other way, he saw my car, gave it the thumbs up, I gave him the thumbs up back, he rode by my car, gave it a side shot, and when I looked at my rear view, he was nodding his head up and down and gave me another thumbs up. I was soooo stoked. And since I live up in the boondocks now, I got amped and had a fun rally cross type run at speed on my way home. Man I love this car.
 

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I didn't see spikes as you describe when I had my TurboXS MBC. Sorry to ask; but you are 100% sure it is installed correctly? You got the in/out hooked up correctly and you completely bypassed the OE boost control solenoid? That's the only thing I can think of that would make it behave badly.

-Pace
 

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Pace,
Yes it was installed correctly. It was running fine for about a month. But 2 days ago, the boost started to flutter. Lioe when a carburated car has a clogged fuel filter, it started to flutter, and would go to full boost, then flutter a bit, and then full boost. I checked all the lines to the boost controller for leaks or cracks in lines and found none. I would really like to go for an electronically controlled Boost Controller or a Boost Monkey configuration. What do you guys think?

I am really interested in the Blitz SBC-ID. Anyone out there have one? Opinions on this sort of boost controller? I just like the idea of having control over your boost from inside the car, and being able to turn it up or down whenever needed.

Anyone else have suggestions? It takes a long time to get through each gear now since I took out my MBC. Boy do I miss it already. Any help or suggestions or opinions will help me.

Kurlee Daddee
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KurleeDaddeeWRX said:
Pace,
Yes it was installed correctly. It was running fine for about a month. But 2 days ago, the boost started to flutter. Lioe when a carburated car has a clogged fuel filter, it started to flutter, and would go to full boost, then flutter a bit, and then full boost. I checked all the lines to the boost controller for leaks or cracks in lines and found none. I would really like to go for an electronically controlled Boost Controller or a Boost Monkey configuration. What do you guys think?

I am really interested in the Blitz SBC-ID. Anyone out there have one? Opinions on this sort of boost controller? I just like the idea of having control over your boost from inside the car, and being able to turn it up or down whenever needed.

Anyone else have suggestions? It takes a long time to get through each gear now since I took out my MBC. Boy do I miss it already. Any help or suggestions or opinions will help me.

Kurlee Daddee
(THE ORIGINAL)
I have the SBC i-D and love it. The funny thing is that people who believe in the part-throttle high-boost problem with MBCs always point to an EBC being the solution. This is not so unless you get an EBC that can map boost from TPS, which neither the SBC i-d nor the AVC-R can do. I can easily get part-throttle full-boost with my SBC i-d, but I don't believe it to be a problem anyway.

The advantages of running an SBC i-D:

- Great boost response and control. The least spikes of any boost controller (according to SCCs testing). This is largely due to the twin solenoid mechanism.
- Four channels = four preset boost configurations.
- Adjustable gain so you can determine how fast you want boost to build. The higher the gain, the faster the boost response, but the more likely you are to briefly spike past your target.
- I can hold full boost all the way to the redline with my VF30. I could not achieve this with the OE boost solenoid.
- Easy to adjust on the fly, in the cabin.
- With the optional harness, will display ECU parameters.
- Can display manifold pressure in just about any units imaginable.


Anyway, I'm not sure what's causing your fluttering problem. The bleed screw didn't work its way loose, did it? If you don't want to spend on an EBC, you might want to go with a ball-and-spring type MBC. The SCC tests actually favored this type of MBC over some of the cheaper EBCs.

-Pace
 

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Thanks for the info pace, I really appreciate it.

Also, I took apart my MBC and it seems that the person I bought it from (it was used) had tried to seal the cap screw at the bottom end with RED liquid loctite instead of plumbers tape and maybe got like 2 or 3 threads worth of sealing. I took the whole thing apart, replaced the plumbers tape on both bottom fittings(one cap screw and one nipple fitting) and put it back together. I will buy new hoses for it tomorrow, put it back on and see if it still flutters the boost. If it does, it will go in my desk drawer with all the other car parts that don't work.

Kurlee Daddee
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russ said:
Maybe check the hose connections, too.
Russ,
The hose connections were fine. I made that mistake the first time I installed the MBC. But it worked fine for a whole month, and then started fluttering. I will be reinstalling it on Saturday with new hoses, just in case the ones I have are cracked (used hoses too.)

Kurlee Daddee
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pace, tell me why i should the get sbc rather than the avc-r. i like the apaexi display more, and the more flexible boost control. i know the dual solenoid issue, but how big of a difference will i see there?

dR
 

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dark_rex said:
pace, tell me why i should the get sbc rather than the avc-r. i like the apaexi display more, and the more flexible boost control. i know the dual solenoid issue, but how big of a difference will i see there?

dR
SBC ID looks more user friendly imo. Also you don't have to scroll around all over the place to change settings. I'm not pace though.;)
 

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TurboXS MBC

Hey I was wondering if anyone has used the TurboXS Standard MBC. Is it any good? I can get one brand new for $60 bucks so I was wondering if its just as good as the Joe P. Please let me know and dont let price be the factor of your choice. Thanks!
 

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