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Hi all... I am new to the sit 2010 MAZDASPEED 3 is my ride. My mod's. Cork Sport inlet air intake, Cork Sport cat back exhaust, and Cork Sport race pipe. I have an HKS ssqv3 on the way and should have it by Tue Wed next week. I was just wondering what it would take to run this BOV vent to att. I know the car very well because I used to sell them. But!!!!!! I just started moding my Speed 6 weeks ago. Any help would be awesome
Thanks..
 

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[quote author=Kendallanimal12 link=topic=80641.msg4008993#msg4008993 date=1304208747]
Hi all... I am new to the sit 2010 MAZDASPEED 3 is my ride. My mod's. Cork Sport inlet air intake, Cork Sport cat back exhaust, and Cork Sport race pipe. I have an HKS ssqv3 on the way and should have it by Tue Wed next week. I was just wondering what it would take to run this BOV vent to att. I know the car very well because I used to sell them. But!!!!!! I just started moding my Speed 6 weeks ago. Any help would be awesome
Thanks..
[/quote]

Since these vehicles run on a MAF it's unlikely that you'll get a VTA valve to work properly, so the cars performance and driveability will suffer greatly; there is also no real gain to running a valve VTA. You could convert to Speed Density using a MAP sensor, but a system like AEM, for instance, is costly and for the power levels you'll be making, it's definitely not worth the money. Stick to Recirc, keep it simple and affordable.
 

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[quote author=Ramen_Noodle link=topic=80641.msg4010250#msg4010250 date=1304360765]
[quote author=Kendallanimal12 link=topic=80641.msg4008993#msg4008993 date=1304208747]
Hi all... I am new to the sit 2010 MAZDASPEED 3 is my ride. My mod's. Cork Sport inlet air intake, Cork Sport cat back exhaust, and Cork Sport race pipe. I have an HKS ssqv3 on the way and should have it by Tue Wed next week. I was just wondering what it would take to run this BOV vent to att. I know the car very well because I used to sell them. But!!!!!! I just started moding my Speed 6 weeks ago. Any help would be awesome
Thanks..
[/quote]

Since these vehicles run on a MAF it's unlikely that you'll get a VTA valve to work properly, so the cars performance and driveability will suffer greatly; there is also no real gain to running a valve VTA. You could convert to Speed Density using a MAP sensor, but a system like AEM, for instance, is costly and for the power levels you'll be making, it's definitely not worth the money. Stick to Recirc, keep it simple and affordable.
[/quote]
Sweet. Thanks alot man!!!! I will be putting it in tomarrow. :p :p :p :p
 

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All right. So I put my new HKS SSQV on today :p Great product. I now have all off my psi back. No leeks. I have seen that a lot of people say not to run this BOV in VTA mood. I am having no issues running it this way at all. I have installed it both ways and have noticed no diff?? Anyways it is rock solid and works great :lol: :lol: :lol:
 

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I actually made this post for another thread. However, I feel more than just the subscribers to that thread can benefit greatly from this post. There seems to be some misconceptions about the way these things work. So here it is. Feel free to let me know if I need to add/address anything!

What is the function of these valves? A turbocharger compresses air with the help of exhaust gases... Just because you let your foot off the gas, that doesn't mean boost building is stopped. That excess boost has to go SOMEWHERE. The factory valve reroutes it to the intake. Atmospheric valves, vent to atmosphere, and hybrids will do a bit of both. I will post diagrams I mocked up, and go from left to right through the illustrations, describing each condition with each type of valve. I hope this helps illustrate WHY a BOV is potentially harmful, while BPVs and Hybrids are not.

STOCK BPV:

* When the throttle is open - The piston is not under pressure, so the compressed air from the turbo flows right through.
* When the throttle is closed at low boost levels (Example: Shifting around 2200 RPM) - The piston is under light pressure, and the stock spring is not very strong, so that excess air is effectively routed back to the intake tract. (The MAF sensor expects this excess air to be plumbed back to the intake, so the ECU demands more fuel to balance the A/F ratio.)
* When the throttle is closed at high boost levels (Example: Shifting around 4500 RPM) - The piston is under heavy pressure, so that excess air is effectively routed back to the intake tract. (The MAF sensor expects this excess air to be plumbed back to the intake, so the ECU demands more fuel to balance the A/F ratio.)

ATMOSPHERIC BOV:

* When the throttle is open - The piston is not under pressure, so the compressed air from the turbo flows right through.
* When the throttle is closed at low boost levels (Example: Shifting around 2200 RPM) - The piston is under light pressure, and the since the spring is heavier in aftermarket applications, the excess air creates a back-pressure by having nowhere to go other than back where it came from... The turbo's compressor wheel is forced to spin backwards. This is referred to as Compressor Surge. This can seriously damage your turbo over time. The second ill effect is that your ECU has demanded fuel, but that air is not routed back to the intake, thus causing an extremely rich moment between the shift (Often resulting in a fire ball out the exhaust).
* When the throttle is closed at high boost levels (Example: Shifting around 4500 RPM) - The piston is under heavy pressure, and the piston moves far enough to expose the opening and vents that excess boost off to the atmosphere. This creates a very rich moment during the shift, because your ECU has demanded fuel, but that air is not routed back to the intake, again causing an extremely rich moment between the shift (Often resulting in a fire ball out the exhaust).
Additional Notes - If the valve is adjusted to a lighter spring tension, you will effectively prevent the backspin, but it will also allow the piston to push too easily creating boost leak, before you even reach your target boost pressures. Now you may think you have a "perfectly tuned" the valve.. But this is VERY unlikely, because boost pressures vary. Your valve's spring will ALWAYS be too strong or too tight. Causing boost leak, or compressor Surge, and always leading to that rich mixture between shifts.

HYBRID or 50/50 BOV:

* When the throttle is open - The piston is not under pressure, so the compressed air from the turbo flows right through.
* When the throttle is closed at low boost levels (Example: Shifting around 2200 RPM) - The piston is under light pressure, the piston is only pushed far enough to reveal the first opening which routes the excess boost to flow back to the intake. (Just like stock)
* When the throttle is closed at high boost levels (Example: Shifting around 4500 RPM) - The piston is under heavy pressure, and the piston moves far enough to expose both openings: theoretically this satisfies the plumb back to the intake, and then vents off any additional boost off to the atmosphere.
Additional Notes - The idea behind a Hybrid valve is simple and effective. It's got two openings. One to plumb back to the intake, and one to vent to atmosphere. The Vent opening is further back than the Intake opening, so that under light load and light boost levels, the valve functions EXACTLY like a by pass valve. But once you're shifting under full boost, there is so much pressure that the piston is pushed even further back revealing BOTH openings. Theres only so much boost that first opening can plumb back in that moment, so the rest is vented off to the atmosphere.

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Conclusion - The entire point of this point was to dismiss rumors and hopefully provide some technical insight to those who didn't quite know the difference, or just wanted to know more about the way these valves function. Obviously, the more you know about a product, the more of an educated decision you can make while being aware of any potential gain or harm. If there's any biased message, it's that Atmospheric BOVs are unsafe in applications like Mazdaspeed3s (and most other stock turbo cars). Hybrids are, in theory, the best. The stock BPVs can only hold so much boost because the springs are just strong enough to hold factory level boost (sometimes a tad less, and end up causing boost leaks). Atmospheric BOVs are capable of holding higher boost, but are also adjustable to allow more leak or more resistance. (Again, an 'absolutely perfect' compromise is impossible). Hybrids or 50/50 valves try to give you that BOV sound at high boost levels while effectively functioning like BPVs under lower boost. Boost leak is safer than compressor surge. But neither is really a good thing. One loses power, one harms the turbocharger.

Happy Motoring!
Is there a brand you would recommend and and maybe a post about how to set up the blow off valve? Speed 3 is my first turbo car so new to me
 
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