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So I got a MBC for the purpose of having full boost on all gears. Then my friend told me why dont you just eliminate your boost solenoid on the T all together. His theory is that if I max out at 14.5 or whatever pounds then the waste gate has a 14 pound spring, so if I eliminate the connection to the solenoid and plug the the line from the intake I should be having full boost on all gears. PLEASE TELL ME WHAT YOU THINK ANY INPUT IS WELCOME.
 

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You can bypass your factory boost controller solenoid but you really should retune to make its working properly. You leave it connected to the to the harness so you dont throw any check engine lights. Right now im bypassing it but running straight off my external wastegate.
 

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yeah thats what I ment sorry, he wants to connect the wastegate directly without the solenoid. What problems can come from this.
 

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yeah thats what I ment sorry, he wants to connect the wastegate directly without the solenoid. What problems can come from this.
The biggest thing is tuning for how it will respond. Different boost controls will cause different ways for your boost to react. I wouldn't do it with a manual boost controller due to them just not being very reliable. I've seen first hand where temperature changes cause it to overboost and not hold pressure reliably. If I were you and you want good boost control (and you're going to have to re-tune anyways) get the Grimmspeed EBCS.

Grimmspeed Boost Controller Solenoid (Choose Subaru inside) - $105.00 : Kronos Performance, Leading since 6th Century BC
 

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Your friend is not very intelligent. I'm sorry to say it like that, but he obviously has no idea of how the boost control system in your car works.

Your car maxes at 14.5 PSI because it's tuned to do so. The boost control solenoid is manipulated by the ECU to allow only a certain amount of pressure. Without any kind of intermediate controller, it will either not go past 7psi, because that's the ACTUAL spring pressure in your wastegate, OR it will boost uncontrolled as high as that turbo will go, depending on how it's hooked up. Trust me, you don't want either.

You can go MBC, but you need a tune. You can go with a 3-port solenoid, but you need a tune. You can utilize the stock BCS, and get a tune for increased pressure. No matter what you do here, if you change how the ECU regulates boost pressure, or mechanically alter the boost pressure control system, you need a tune. You can't just modify things on your car and expect everything to work just fine fueling and timing wise. This is how engines are destroyed.
 

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Your friend just told you how to blow up your engine, you need to learn/read a lot more about how engine and boost management works... Taking off the FBC solenoid does one of two things, you will get about 7 psi max, or whatever the turbo is capable of, probably over 22 Psi and you will get fuel cut maybe.... As the ECU will try to save the engine but probably fail... Even with a MBC you can have serious problems without engine management...
 
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