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Discussion Starter · #1 ·
I spoke with a gentleman from TurboXS about their products for our cars. He informed me that although the BOV provides a nice and intimidating sound, he stated that that was merely all you get. I understand the idea of such a device, but he told me (him being a fellow WRX owner too) that the factory BOV provides just as effective relief and no additional spooling times will be saved with the addition of this product to our vehicle. He did state that other applications, such as with Mitsubishi's, generally require BOV's to aid in their poor design - not Subaru. He turned me on to the boost controller, however he encouraged the use of the high performance boost controller for the two-part system safety factor and nice to have when upgrade time comes. Now here's my question...when this device comes, he said it will be set to a setting of roughly 7 psi. What is the factory psi and what/how can I safely adjust to maintain safe engine longevity? Basically, has anyone purchased such an item and worked out the kinks for me? How do you know when you've reached the maximum safe setting given no current upgrades? Thanks in advance for all your help - Chris

By the way, I have the factory gauges - as crude as they are, so can this boost gauge help in the adjustments?
 
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I have a TurboXS MBC installed in mine(about a month now). Very, very simple to install and worth every penny you paid! Basically install the MBC as per the instructions, then turn the boost ALL THE WAY DOWN, I mean clockwise til it won't turn anymore. Make a run down the road and see where your boost is at(you need to hit 4th gear wide open to get an accurate reading). Then for every turn counter-clockwise, it's is supposed to be equal to one pound of boost, which I found pretty much true. Adjust and keep making runs til you're running around 15 PSi, which is safe. Some people even say 16 Psi, but I wouldn't push it too much (maybe at the track) have fun and be safe! By the way, when I installed mine, it shave .7 seconds off my quarter mile time, down to a 14.1 now. Hopefully in the 13's tomorrow, we'll see!!
 

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Discussion Starter · #3 ·
Thanks dowell2244! I'll do that and feather it in. Did you reset your ECU following its installation? I look forward to toying with this new best friend.

Thanks again - Chris
 

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I bought the turboxs boost controller from mark directly at a car event. Really nice guy, he was very honest. HE said that the BOV does throw the car off becuase it doesnt keep the air int he system which the car is used to. It was like a new car when i put it on. I run at maximum boost. You need a boost guage to acurately tune. You will hit fuel cutoff if you boost too high, and you can boost more in 3rd, 4th, and 5th than you can in first and second. Of course it will void the warranty but it comes on and off in like 3 minutes so no biggie there. Best 70 bucks i ever spent.
 

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Originally posted by rx4pain:
I spoke with a gentleman from TurboXS about their products for our cars. He informed me that although the BOV provides a nice and intimidating sound, he stated that that was merely all you get. I understand the idea of such a device, but he told me (him being a fellow WRX owner too) that the factory BOV provides just as effective relief and no additional spooling times will be saved with the addition of this product to our vehicle. He did state that other applications, such as with Mitsubishi's, generally require BOV's to aid in their poor design - not Subaru.


Not true. The aftermarket BOV will help in high boost situations where the stock one will start to leak... in most cars. I have no idea how a stock WRX BOV takes to serious boost (~20 psi or more), but I'm willing to bet that it will, just like all other stock BOVs, start to leak under the pressure... robbing you of boost.

And, BTW, the only Mitsu BOV that suffers from poor design is the 3000GT VR-4 / Stealth TT. Every other turbo car Mitsu makes has good stock BOVs. The 3/S BOVs are good, but honk like a goose when you add on an open air filter. No performance problems, just an annoying loud honking noise. :)

He turned me on to the boost controller, however he encouraged the use of the high performance boost controller for the two-part system safety factor and nice to have when upgrade time comes. Now here's my question...when this device comes, he said it will be set to a setting of roughly 7 psi. What is the factory psi and what/how can I safely adjust to maintain safe engine longevity? Basically, has anyone purchased such an item and worked out the kinks for me? How do you know when you've reached the maximum safe setting given no current upgrades? Thanks in advance for all your help - Chris


A MBC is a great addition. *ESPECIALLY* if your stock boost is ~9 psi. One you run it up to ~14 or ~15 psi it will shock you with the response.

I'm not a WRX expert, nor do I really know much about them, but I'm sure the same adage applies to them that applies to all turbo cars. Get an Air / Fuel gauge and make sure you are not leaning out the stock fuel system.

By the way, I have the factory gauges - as crude as they are, so can this boost gauge help in the adjustments?
As a general rule the factory gauges are based more on a sum of calculations made by different sensors in the system. They are usually more or less an educated guess that is wrong. :) I don't know how Subaru set up the gauge in the WRX, but chances are it's not 100% accurate. The best bet would be to get an aftermarket guage to monitor boost.
 

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Discussion Starter · #7 ·
New information I received from TurboXS. Supposedly the stock boost is approximately 13 psi. On a turbo gauge reading in bars, .1 bar = 14.5 psi. And every 1/5th (considering that the gauge reads in increments of five measurements per .5 bar)is approximately 1.5 psi. Therefore, according to my stock gauge, which appears to be accurate, I'm running at .9 bar, or 13 psi, WOT in fourth gear. That would suffice to say that at .1 I would be running at 14.5 psi by adding the one increment. According to TurboXS, running at 16 psi is a safe maximum barring no additional modifications past intake/exhaust. Just some additional info. in case someone is interested in going this route. Too, I understand that a BOV would be beneficial when running radical boosts, however you would be running a system that more than likely would divert from stock altogether and would include such an aftermarket item.

Thanks for the info - Chris
 

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As long as the stock BOV is doing its job, you dont need a new one. It is simply a sound mod.
The stock BOV isnt going to leak under anything under 20psi, and maybe not even after that.
HE said that the BOV does throw the car off becuase it doesnt keep the air int he system which the car is used to
Only when BOV is set up to vent to the atmosphere. This is due to the fact that the MAF (mass air flow sensor) has already taken into account the air that has entered the turbo, when it is vented to the atmosphere, the engine thinks it has more air than it actually does and dumps too much fuel into the engine. If you set up your BOV to vent back into the intake (like stock BOV) then it will run perfect, but the venting will be much quieter.
 

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btw,
bar is short for barometric pressure.
1 bar is the ambient air pressure at sea level, 14.8 psi. (remember high school physics class?)
 
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