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Discussion Starter #1
I don't believe I've seen anyone ask this yet, but if it's been posted, sorry for being lazy.

Just got an MBC in the mail. I took a look and tore down what we got back there at the turbo. The MBC I got uses 3/16" on both ends. The hose coming off the turbo looked like 1/4"?? See my problem? What should I do to go from 1/4 to 3/16 then the opposite at the other end? I don't know if reducers would be a "reliable" option. I can't find new fittings for the MBC. Other thing is, what kind of hose should I get, and where do you get it? All Autozone and Advance had was rubber fuel hose. Won't that get jacked by the heat and crack or leak?
 

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Simple solution... you need SILICON hosing... when I order my MBC I ordered 3' of silicon hosing in 3/16 i believe it was and it worked out fine. If you can't find any at those auto places, look for a pep boys or go to streetunit.com and get some hoses for cheap, in any color.
 

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Yupe. I put a small SMALL amount of dish soap in the hose on the end... slides on easily... and burns away once the car starts. Harmless.


Quick Edit:: If you are thinking about increasing your boost or holding the boost longer. I would suggest a better BoV... not sure if the stock can handle any more than 15.6psi, especially to redline. Just my 2 cents though.
 

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Yupe. I put a small SMALL amount of dish soap in the hose on the end... slides on easily... and burns away once the car starts. Harmless.
Quick Edit:: If you are thinking about increasing your boost or holding the boost longer. I would suggest a better BoV... not sure if the stock can handle any more than 15.6psi, especially to redline. Just my 2 cents though.
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Anybody else back this up? I'm in the same boat, mbc in the mail, still using stock bov. I only want 15 to 5.5k
 

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I don't think anyone knows how far it will go... but I can tell you judging from members having to replace the factory unit because it couldn't keep up with the factory boost, its holding on to its last leg....

Once you replace it and hold it in your hand, you will know why you replaced it...
 

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im running 16.5 to 17.5 psi with the stock bov no problems. Im gonna upgrade my bov eventually.
 

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Discussion Starter #9
Well this is how the first day with the controller went... Put it on in the morning, set it all the way down and took off. 14 psi to about 5.7k(ish) and it fell to 8 psi near 6.1k. 2 clicks up and got 14.5 psi and the same afterwards. 2 clicks up and got 15-15.5 psi and 10 psi at 6k. 2 clicks up and got 16-16.5 psi and 12ish at 6k. After all that and no fuel cut I took it on the highway. No more spikes in boost and alot better with the drop off in pressure (there is still a drop). So, I pull over and give er another 2 clicks. Mash the pedal at 3k rpm in 5th and it jumped to 18-19 psi and fuel cut near 5k.

By then it was time I head to the track to meet the other speeds. I took it down 1 click and had no problems getting to the track. For some reason on my first run it held 14.5-15 psi dropping to 11-12 by 6k. Hmmm... 2 clicks up (remember this gave me fuel cut) and then it held 15.5-16 falling to 12 at 6k. What the hell 2 more clicks up. It held 17 and fell to 13ish at 6k which netted me a 13.77 1/4 mile.

Here's the wierd part. When I left the track and got on the road I peddled it in 4th and got fuel cut?? For some reason it hit nearly 19 psi !!??? WTF is going on?? Pulled off and toned it down 2 clicks and held 16 psi with no problems. When I got gas near home I clicked it down 3 more times to hold 15 psi.


I have noticed no problems with the stock BOV (yet) taking that abuse today.
 

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Your ECU is still controlling the actuator, that's why you are getting drop off. You need to plug the actuator... here is a pic that shows what I mean. The ECU will still think that it's controlling the actuator, but it will be the MBC as intended.

http://i80.photobucket.com/albums/j164/P5FREEK/MBC.jpg

goodluck
 

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Spooner,

Does your suggested hose routing experience a small drop off in boost as redline approaches? I have yet to install my MBC but I planned to route the boost side of the MBC to the intake mani to negate IC pressure drop.
 

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I wasn't able to get the car to hold boost til redline and that makes me wonder if the stock BOV is the problem...
 

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Spooner,

Does your suggested hose routing experience a small drop off in boost as redline approaches? I have yet to install my MBC but I planned to route the boost side of the MBC to the intake mani to negate IC pressure drop.
[/b]

I hold to red-line... absolutely NO drop off.
 

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Discussion Starter #14
Your ECU is still controlling the actuator, that's why you are getting drop off. You need to plug the actuator... here is a pic that shows what I mean. The ECU will still think that it's controlling the actuator, but it will be the MBC as intended.

http://i80.photobucket.com/albums/j164/P5FREEK/MBC.jpg

goodluck
[/b]
There's only 2 hoses coming off the actuator. 1 to the turbo and 1 to the solenoid. I plugged the top of the actuator and 1 of two hoses on the solenoid. I've done everything right as far as what I've read on the forums (and from P5freak), but am still getting boost fall off near 6k. Is the BOV leaking this added pressure back into the intake?
 

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thekorean what was your mph with the extra boost to redline? How did the extra little boost feel from the drivers seat and I assume you could tell the difference?
 

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Discussion Starter #17
thekorean what was your mph with the extra boost to redline? How did the extra little boost feel from the drivers seat and I assume you could tell the difference?
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My runs were...

Run 1 Run 2 Run 3 Run 4
Reaction 0.413 0.557 0.768 0.459
60 ft 2.421 1.972 1.829 1.864
330 ft 6.445 5.854 5.629 5.62
1/8 ET 9.69 9.042 8.791 8.755
1/8 MPH 75.42 76.66 77.04 77.66
1000 ft 12.484 11.798 11.521 11.481
1/4 ET 14.837 14.125 13.83 13.77
1/4 MPH 94.9 96.69 96.59 98.3

I copied this from Excel... It's not going to look better than that. Unless someone is bored and can put it in a table..

Before I put the controller on my best time was 13.9x. Remember I'm still having troubles getting it set right and it's not holding consistent boost to redline. But, for $60 on Streetunit.com you can't beat it.
 

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Wow I figured since you are holding more boost your MPH should have been a bit higher. 98mph is good I just figured it would be right at 100+mph. My previous highest mph was 98mph and I do not have a boost controller. NO big deal I was just thinking it would a bit higher.
 

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Discussion Starter #19
Wow I figured since you are holding more boost your MPH should have been a bit higher. 98mph is good I just figured it would be right at 100+mph. My previous highest mph was 98mph and I do not have a boost controller. NO big deal I was just thinking it would a bit higher.
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"Remember I'm still having troubles getting it set right and it's not holding consistent boost to redline. "
 

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alright guys, anybody have a suggestion on the easiest way to access the actuator hose on the turbo? im a skinny chinese guy and im still having trouble getting to the clamp.
 
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