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Discussion Starter · #1 ·
I just received my Joe P manual boost controller in the mail. I didn't want to put it in just yet, but I went poking around under the hood to try to figure out where it goes. There's a lot of vacuum lines under there!

Can any one who's fitted an MBC to their car help me with the proper location for hooking it up?

-Jim
 

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i thought it would come with instructions. can you post it when you find out? mine will be here soon.
thanx
 

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There is really no need to plug the stock hoses as they will no longer be connected to anything within the boost control loop.
 

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Discussion Starter · #5 · (Edited)
I'm going to break down the manual boost controller install into steps for those new to MBCs like I once was. In general, MBCs like the Joe P or a homemade unit are a valve that only opens when it reaches a desired pressure. An electronic solenoid unit (stock or aftermarket) goes in at the T between the wastegate and the high-pressure nipple from the turbo. The solenoid remains open, bleeding off boost pressure until the computer tells it to close, which sends the pressure through the line to the wastegate actuator. The stock wastegate has a 9psi spring in it, allowing the solenoid to open the wastegate at as little as 9psi.

Before doing the install below, make sure your boost gauge is accurate. You should see about 60% of max in first gear, 90% of max in second gear, and full boost in third through fifth. Maximum boost can be between 13.5 and 14.2 psi depending on your altitude and the resulting atmospheric pressure.

1) Here's a pictorial of the stock (electronic solenoid) setup:
Code:
                Solenoid
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Hi-Pres. Nipple--------Wastegate Actuator
2) Remove the Solenoid hose from the T, tie it up somewhere out of the way. You can, but don't have to, plug it. This hose becomes completely vestigial after you install the boost controller.
Code:
                Solenoid
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Hi-Pres. Nipple--------Wastegate Actuator
3) Remove the T-junction and hoses from the high-pressure nipple and wastegate actuator.
Code:
                Solenoid
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Hi-Pres. Nipple-       -Wastegate Actuator
4) Install the inlet of the MBC to the high-pressure nipple and the outlet to the wastegate actuator. The solenoid has been removed from the air circuit and the pictorial for clarity:
Code:
Hi-Pres. Nipple---MBC---Wastegate Actuator
5) Secure all of the hoses with zip ties because there will be a lot of pressure developed in these hoses (full boost pressure) now.

6) Tune the boost controller, as needed, being careful never to hold 17psi with the stock turbo! Spikes above 17psi should present no problems. I have my Joe P set for 16.5psi in third and I?ve been running it since 4,000 miles with no issues.

-Jim
 

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ohhh, that was mean Plat, hehe
 

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Which tube is inlet an which is ouput on the MBC?? We think we have it right but I want to make sure before I blow my engine.
 

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Ok, I have the hoses right. I had them backwards and my check engine light came on but i switched it to the right way and it turned off. Is that normal if you have them the wrong way?
 

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Discussion Starter · #11 ·
str said:
Ok, I have the hoses right. I had them backwards and my check engine light came on but i switched it to the right way and it turned off. Is that normal if you have them the wrong way?
Yes, the wastegate won't open, so you'll get a CEL.

-Jim
 

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FINNALY!! I got it. thanks for everyone's help on this, sorry for all the questions. All I have to do know is get s a longer hose so i can mount it where I want and I'm set. My poor car, I felt like I had to keep driving it hard to keep reading the boost guage to get the setting right. It needs a break.
 

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3 questions, first is do you retain the factory hoses or use the ones that came with the Joe P. Second what do you use to clamp the hoses on the nipples, the stock metal ones look to small for the hoses the Joe P came with. Am I supposed to use the zip ties for this and just pull them really tight. Also when first installing the MBC should the adjusting screw be all the way down and tightened and then adjust from there. Mine came a little loose and I wanted to make sure the first time I try it I don't over boost.

Thanks
Bryan
 

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PlatinumWRX, THANK YOU FOR THE WRITEUP! (sorry for the caps, I'm exuberant :). That was my bible when I threw the JoeP 2nd Gen MBC in a couple of nights ago and it went PERFECTLY. Have you thought about a career as a technical writer? Excellent!

Kanos,
I used the hoses that came with the JoeP... I used the zipties to hold everything together, but I would feel more confident running hoseclamps. I'm going to look for some when I get a chance.
You want the adjusting screw as far OUT as possible. Dialing the screw IN (clockwise) INCREASES boost. Dialing the screw OUT (counterclockwise) DECREASES boost.

Think of it as "SQUEEZING" in the boost to make it easy to remember. You release the tension to lower the boost. That's how I remember it off the top of my head. :D

BTW, when I was adjusting the MBC - I had 3-4 runs where I had only 9PSI of boost because the MBC wasn't bleeding any boost at all with the adjusting screw as far out as I had it. However, I was taking the safe route. I had the screw only held in by a couple of threads - and then made a run. 9psi. Screwed it in 1 turn and made a run. 9psi. Screwed it in 1 turn and made a run. 9psi. Screwed it in 1 turn and made a run. 9 psi. Screwed it in 2 1/2 turns. 17+ PSI. DOH! Turned the screw OUT 1 turn. 16 psi. Turned the screw OUT 1/4-1/2 turn. 15.5psi, WOT at 4k rpm is 3rd gear.

Please note that not all cars are going to respond the same way, and please don't use my adjustments to set your MBC without being safe first and running through the "no boost" stages.

I had an idea during my install that would make installation easier (at least setting a baseline to eliminate the first 3-4 no increased boost runs) - but couldn't pull it off because I didn't have the tool with me.

Why don't people plug the bleed hole on the MBC, and then use a MityVac tool and push 14-15psi on the hose that goes IN to the MBC (the one that would hook up to the high pressure nipple on the turbo outlet) and adjust the screw in until the pressure dropped on the MityVac gauge?

Just a thought... Good luck, All! I LOVE MY JOEP!

Aloha,
Richard...

P.S. I'm always having to devote a spare eye to my boost gauge as it's REALLY easy to get into PTFB situations. I'm not sure I totally buy into all the doom-and-gloom hype about the damage that can be caused by that situation - but I'm not going to test the theory on MY car. :p
 

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how quick after ordering did you receive the product? i have a local vendor that is selling one for $75. i am debating whether to save money or save time waiting.

the one locally is a different brand. not JoeP.

thank you.
 

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Discussion Starter · #16 ·
jorge02wrx said:
how quick after ordering did you receive the product? i have a local vendor that is selling one for $75. i am debating whether to save money or save time waiting.

the one locally is a different brand. not JoeP.

thank you.
Joe P was $48 and arrived in two days. If you can't wait two days, you've got issues with patience.

-Jim
 

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Thanks for all the great help, I think I will take an hour in the morning before work and try installing it.

jorge02wrx, I ordered mine friday morning, got it monday, so if you order it tomorrow morning you might get it the next day, or at the latest Friday.
 
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