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Discussion Starter · #1 ·
I am going to install my DMBC and on several instructions it says to connect the MBC thru the BOV. I already have my boost gauge running off of the BOV so is it going to be a problem to put another "T" into the line. If I do where should I put it. Here are some links and pics of what I am talking about.


http://forums.nasioc.com/forums/showthread.php?s=&threadid=215050&highlight=Grainger+Solenoid


http://www.clubwrx.net/forums/showthread.php?s=&threadid=11523


http://forums.nasioc.com/forums/showthread.php?s=&threadid=198959&highlight=dual+and+boost

Any help would be appreciated
 

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well, an easy way to locate the first hose if you haven't worked on the car b4 is to open the hood, look at the engine, and direct your sight towards the passenger side strut tower(suspension). Right in front of that, there is a plastic cover which hides some sensor wire, and the factory boost control solenoid. This solenoid is a valve with some wires and 2 hoses coming off of it....... One hose goes to the T fitting on the turbo, and one goes to the turbo inlet pipe(intake pipe between turbo and filter). Trace the hoses till you find the one that goes back to the turbo and remove it, the T fitting, and the two other hoses on the turbo.

Put a new hose going from the metal 90 degree nipple on the inlet side of the turbo to the dualmbc, and put a hose from the mbc to the wastegate actuator on the turbo(the actuator is more on the passenger side of the car, both had the small hoses on them). Then ya need to send the wires back into the cabin. There is a port right behind the intercooler which goes into the cabin, and once it goes through, you can usually see the stuff you pushed through from under the steering wheel. Wire it up to a ground and the ignition, close both of the valves all the way, and start adjusting boost:). I think that's how to do it. Don't loose the hoses that were on the turbo or the one that went from the turbo to the bcs. There is a little brass restrictor in one of the hoses, and if you want to return your car to stock some day, you will need it.

To adjust the boost, make sure you're on the first setting, and find an onramp to a highway(or something). Pop the car into gear and get it into fourth or fifth(if you set the boost in fourth, you will not want to push the car in fifth unless you make fifth your second boost setting). Anyways, open the first valve til your get the low boost setting you want at 3500rpm in fourth(or fifth) gear. Once you set that valve(if you change the fist one, it will change the boost of the second setting), click the sweeeetch, and start openning the second valve until you get the high boost you want. If you wanted to get the same boost in fourth and fifth, you'd set the low boost to fifth gear, and the high one to fourth(from what I hear). If you set the boost in 1st or 2nd gear, you might get more boost in every gear after that(cause there's more load).

peace

 

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Discussion Starter · #3 ·
Thanks but that didn't help much. I am using a Grainger soleniod and making my own BC. It will enable me to switch between stock boost and the MBC. With this setup you use the original "T" hose. I already have a MBC but just want to add an on/off feature. I understand how to hook everything up except the BOV. Where does the BOV hose run to? and is it ok to run the 2 "T's" off of the one hose coming from the BOV?
 

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yeh, I was way off I guess. They use the bov vacume line for pressurizing the wastegate line while using the mbc(it seems). I would think this might have some ill effect on the performance of you car while in mbc mode....... I dunno what to tell you except I'd do it much different:). I'd get 2 solenoids.

I'd start by placing one vacume line from the turbo to the first solenoid. One line from the solenoid to the mbc and one from the mbc to the next solenoid. The second line from the first solenoid would have the brass restrictor in it, and go into the factory T fitting. One line coming off the fitting would go to the bcs and the second line would go to the second solenoid. The second solenoid would have a line to the wastegate actuator. The switch would change both of the solenoids from mbc to factory bcs(and the other way around). It might cost a little more for the second solenoid, but it won't screw up your bov or boost performance.......or I could just be missing something:).

peace
 
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