gogogomoveit
Member
Well i guess thats exactly the point of running a aftermarket BOV?(hah)
Which blow off valve to get
- Thread starter high3at0209
- Start date
Well i guess thats exactly the point of running a aftermarket BOV?(hah)
Saskatchewan17
Member
- :
- 2008 TR Mazdaspeed 3
Not necessarily:
http://www.youtube.com/watch?v=nB1wnKdIT10
http://www.youtube.com/watch?v=ws4zEXQnnYA&feature=related
Both in recirc and you can hear them loud and clear. No point in running a BOV VTA in this car unless you have SB and can tune out the rich fuel mix between shifts. Even then, it's kinda stupid.
gogogomoveit
Member
I guess everyone is entitled to the right of how to modify their cars.
For the record, the stock BPV leaks by DESIGN, not by flaw. Forge is best bang for your buck, and like previously mentioned in the thread, will easily pass as the stock valve should you be concerned about warranty. Avoid synchronic as they're over engineered and not worth it. I've heard bad things about the greddy ones, but nothing really conclusive. I have HKS SSQV V2, and I bought it cause I like the noise. Have had 0 issues with it, and car holds boost flawlessly.
At the end of the day, listen to videos/sound clips of different valves and find one you like. There really isn't one specific valve that will perform better or worse IMO (aside the ones I mentioned which are just poor quality).
EDIT: Oh, and don't get anything VTA as the car will run like absolute asshole unless you plan on getting it tuned.
At the end of the day, listen to videos/sound clips of different valves and find one you like. There really isn't one specific valve that will perform better or worse IMO (aside the ones I mentioned which are just poor quality).
EDIT: Oh, and don't get anything VTA as the car will run like absolute asshole unless you plan on getting it tuned.
I'm on stock BPV. I spike to 21 psi (due to catless dp/rp) and hold steady at 17 psi, sometimes 18 in cold weather. 18 means load cut.
My point is that it does not leak, by design or otherwise. It is smoother in its release than abrupt aftermarket valves. That is a difference. This means it may come up on boost a bit slower in first and second gear and seem a bit less "lively." But since we have too much power and easily overpower the tires in those gears, I do not consider this a liability.
Objective tests of the Forge by Grass Roots Motorsports mag actually showed the stock valve holding up to 19 psi in third and higher gears, about a pound or bit more than the Forge.
Note the third gear boost levels as rpm climbs in the attached chart from that study.
Edit: corrected some typos.
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BillTheCat
Member
- :
- 2009 Mazdaspeed3 Sport
I personally only swapped out for a Forge because my Dashhawk revealed that the stock unit was failing to hold much more than 12psi- obviously a defect. The Forge easily holds 15 psi, and 16 is not unusual.
And this bears repeating- if you want to hear the BPV/BOV, you don't need to run VTA. A SRI/CAI will enhance the "whoosh" quite nicely, and in the case of the Forge, also the "ping." On my Supra, I run an HKS SSQV in VTA mode, and it's no louder than my Forge + Cobb SRI combo on the MS3.
Of course, the SRI/CAI route has the added bonus of opening up the car's sinuses & letting it breathe better, resulting in a nice hp/performance bump as well. And by remaining in recirc mode, you're not screwing up AFR's & confusing the poor little ECU.
Not telling anyone not to run VTA- do what makes you happy. Just do it while fully informed that you have options that are less traumatic to the car.
And this bears repeating- if you want to hear the BPV/BOV, you don't need to run VTA. A SRI/CAI will enhance the "whoosh" quite nicely, and in the case of the Forge, also the "ping." On my Supra, I run an HKS SSQV in VTA mode, and it's no louder than my Forge + Cobb SRI combo on the MS3.
Of course, the SRI/CAI route has the added bonus of opening up the car's sinuses & letting it breathe better, resulting in a nice hp/performance bump as well. And by remaining in recirc mode, you're not screwing up AFR's & confusing the poor little ECU.
Not telling anyone not to run VTA- do what makes you happy. Just do it while fully informed that you have options that are less traumatic to the car.
Heh.
Mine must be defective because it doesn't leak.
There is a lot of misinformation floating around. Don't believe everything that you hear.
well I was looking into getting the dual port but after reading this thread I think I will just stick with the Forge BPV. I have a 2010 MS3 with the MS CAI and a Cobb TIP and I have noticed the delay in turbo spooling after these mods. I am not saying I am an expert and can blame that stock BPV but before adding these mods I didn't even notice this problem if it was happening. All being said, I think just replacing the stock BPV with the Forge won't hurt from everyone's opinion but at the sametime I am not tuner enough to get a VTA solution. Thanks for all the advise peeps!
A tuner can't give you a VTA solution either. They might say they can, but they are still just making a correction judgment based on averages for a value that is constantly changing based on a huge number of variables as to how much air gets dumped during a shift. It's never going to be the same.
Only way to run VTA and get correctly metered air is to move the MAF sensor to the pressurized (boosted) side of the intake tract and convert it to a blow through MAF with complete recalibration and a totally different custom tune. That is a huge and expensive undertaking, IMHO, not to be done unless you are upgrading to a bigger turbo, different manifolds, making custom pipes, etc. Otherwise it's just guesswork, conjecture and GFL. A custom tune might smooth out some of the low speed roughness, but it is still not going to be metering correctly.
Only way to run VTA and get correctly metered air is to move the MAF sensor to the pressurized (boosted) side of the intake tract and convert it to a blow through MAF with complete recalibration and a totally different custom tune. That is a huge and expensive undertaking, IMHO, not to be done unless you are upgrading to a bigger turbo, different manifolds, making custom pipes, etc. Otherwise it's just guesswork, conjecture and GFL. A custom tune might smooth out some of the low speed roughness, but it is still not going to be metering correctly.
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ms3brendan
Member
I think I am going to be doing the same thing. The Forge makes one crazy sound though.. I dunno how much I like it.. But it's definitely the cheapest & safest solution for aftermarket BOVs.
bnr32_coupe
Member
that seems like a good price. there's a lot of fake ones out for like $80, with fitment issues and stuff
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Since when would having a faulty BPV start causing boost spikes? Maybe a loss of boost for a failed open valve, but your not going to "overboost" because of a blow off valve.
Only thing that's going to cause that is the turbo wastegate.
I will agree with some of the posts on this regarding the return spring strength on the stock unit. Partial throttle lifts (on and off) are much more noticeable (kind of a jerking feeling) when I'm running the stock unit. With the aftermarket re-circed one I have, it definitely feels much smoother in those crucial throttle plate transitions (same gear on/off, and partial boost gear changes). I've changed several times now for dealership visits and there is a noticeable difference for me.
Only thing that's going to cause that is the turbo wastegate.
I will agree with some of the posts on this regarding the return spring strength on the stock unit. Partial throttle lifts (on and off) are much more noticeable (kind of a jerking feeling) when I'm running the stock unit. With the aftermarket re-circed one I have, it definitely feels much smoother in those crucial throttle plate transitions (same gear on/off, and partial boost gear changes). I've changed several times now for dealership visits and there is a noticeable difference for me.
ms3brendan
Member
I heart my forge
My Forge will be getting here in a few days. What are you running on it? I hear the blue spring + 2 shims is a good setup?
ms3brendan
Member
I got my Forge BPV on! Here's a video clip of what it sounds like in the car with the windows down..
http://www.twitvid.com/VQA8R
http://www.twitvid.com/VQA8R
WhoKnowsWho
Member
- :
- 2007 Mazdaspeed 3
I'm running my forge with just the blue spring. Haven't played around with the shims or anything. Been happy with it as is.
Isn't there a few tuning systems out there that let you shut the injectors off between shifts so you can vta?
Also, does anyone have any experience with the cpe hks unit? I have a cpe nano and it's a well crafted piece, but there bov kit seems expensive and I don't see why, is that flange they make for it really worth the money?
Also, does anyone have any experience with the cpe hks unit? I have a cpe nano and it's a well crafted piece, but there bov kit seems expensive and I don't see why, is that flange they make for it really worth the money?
