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I am looking for some advice on how to best improve acceleration in the low gears/ low RPM's. I was hoping for something fairly inexpensive, safe (I don't want to destroy the engine) and easy to install. I am not mechanically inclined and the most drastic modification I have ever made to a car is to install a short-throw shifter in my WRX. Based on what I've been reading in other posts, it appears that a Manual or Electronic Boost Controller may be the answer? Could those of you who have one of these please give me a quick lesson on how it works? easy to install ? necessary precautions? Do I need a turbo or boost gauge?
cost?
thank you very much:D
 

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How it works?

On the stock system, when exhaust flows through the turbine, the compressor makes boost pressure. There is a hose that comes off the turbo outlet and connects to the wastegate actuator and the boost control solenoid. This hose is usually vented/at atmospheric pressure, so the wastegate actuator is at atmospheric pressure. When boost pressure increases and reaches the point the ecu wants to limit boost, it signals the boost control solenoid, which cycles shut/open. This means the hose attached to the wastegate actuator varies between ~14psi/0psi. Any pressure felt by the wastegate actuator that is more than the actuators spring pressure (7-9psi) causes the actuator to open the wastegate. This lets some exhaust gas bypass the turbine wheel, meaning the turbo spins no faster than it's already spinning.

An MBC is a very simple device. They can be made fancy, but it's basically a spring loaded ball valve. Two pipe fittings with a ball and a spring between them. Air cannot pass through until the air pressure is great enough to overcome the spring pressure holding the ball down. It is installed between the turbo outlet nipple and the wastegate actuator. Just cap off the hose to the stock boost control solenoid. Now, as boost pressure is building, no air is bleeding out and no signal is applied to the wastegate actuator. When boost pressure reaches the point you've set the MBC at, there is now enough pressure to lift the ball, and air flows. Since the wastegate actuator is seeing a pressure more than it's spring pressure, it opens the wastegate.
 

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Yes, it is easy to install.

You *must* first have a boost guage before you play with a boost controller. Most EBC's will have a boost display, but I'd still want a separate guage.
 

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Best way to eliminate lag is to get boost controller and uppipe. Just remember, you need boost gauge before you even start to mess with increasing boost. Some elctronic ones have a built in boost gauge. Uppipe requires no gauge. Simply bolt into place although getting to it isn't exactly easy. It's an all day job.
 

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why is it an all day job? what do you have to do to get to the uppipe?

BTW: God, i got my wrx. ill be waiting for you to release your downpipe :)
 

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JDM spec downpipe fixture is done. I'm just waiting on the flanges and I'll start stocking up. My uppipes were officially released yesterday after successful test fitting on two cars.
The reason the uppipe is a pain is not because it's that hard getting to it. It's because Subaru used the cheapest bolts ever on the car and you'll run in to many which are seized, streched, stuck, etc. . .
 

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god, how much for the uppipe and for the bpipe? what do u think of the blitz nurspec universal? thats what i plan on putting on. and is your site up yet?!?!
 

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God said:
It's because Subaru used the cheapest bolts ever on the car and you'll run in to many which are seized, streched, stuck, etc. . .
I'll second that, and add that they'll also be galled, cross-threaded, over-torqued, stripped, and generally AFU.
 

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oooh, its the downpipe, my bad. ill email you about it later cuz im not gonna buy exhaust for a while, heh. but is the blitz nurspec cat back good? and is it released yet?
 

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I am NOT designing my downpipes to work with the stock exhaust folks. Just letting you all know. The stock b-pipe is pretty small so it may or may not work. The US downpipe will be the right length though. As for the Blitz, you can order the JDM spec Blitz exhaust and use with my JDM spec downipipe if you wish. Blitz will release a US version in the future but might take a while.
 
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