Holding Boost

[Piper86]

Hi all

Car: 2006 Subaru Impreza STI EJ257
Current mods: Manley pistons
Turbo back straight pipe Exhaust with HKS silent hi-power muffler
Cosworth panel dry air filter (*new)
Perrin turbo inlet hose (*new)
Perrin AFTA MAF hose (*new)
NGK one stage colder plugs (*new)
Catch can installed

Custom map (being remapped after *new parts were installed)

So I think the above explains where the car is standing at the moment. I'm currently planning ahead and starting to think about adding a aftermarket recirculating blow off valve (BPV) and a boost controller to the mix in the coming year.

I looked into the following two;
Perrin Recirculation Blow Off Valve (# PSP-TAC-600RD)
Cobb Tuning XLE Bypass Valve (#712660)
As they are upgrade and replacement parts for the OEM BOV.

Also looked into the Perrin EBCS PRO and the COBB Tuning 3-Port Boost Control Solenoid.

As I already have a few Perrin parts installed I am leaning towards sticking with the brand but I'm also open to top quality alternatives.

Do any of you have experience with these parts? pro's and con's?

Reason for looking into the BPV, holding boost, smooth out power curves and getting rid of possible turbo fluttering. My car will only be returning to me in the coming week which is when I will be able to see the dyno graphs and curves.

Reason for looking into the Boost controller: possibly running two settings (high & low boost) and also to smooth out the power curves.

My goal is a reliable, dependable and "economical" (for what its worth) car which has smooth pulling power throughout the rev range.

 

[HolyCrapItsFast]

I assume this is a stock turbo?

To be completely honest if it aint broke don't fix. Meaning you will not see any noticeable gains from a BPV unless you have a reason to replace it. For a stock turbo the stock BPV is the absolute best. A BPV will not help you hold boost but may help you improve shifting if you get the right one and can adjust it to allow you to compensate for a variety of issues. For holding boost you would need to look into a larger turbo. The stock one runs out of steam quickly and tapers regardless of how much you adjust boost control.

The same philosophy can be applied to the EBCS as well in that, if you are achieving boost targets then job done. The boost control system in the ECU is wildly capable of tailoring the boost curve for strategy tuning even with the stock EBCS. You just need to find a tuner that knows how to do it. The moment I would replace the stock EBCS is when you need more than 85% waste gate duty to achieve your target boost but even that is not absolute. The turbo itself could be the determining factor there.

As for brands I think pretty much all of them are overpriced toys at best. Especially when it comes to the EBCS. You could buy a MAC pneumatic valve from eBay complete with fittings, brackets and connectors for less than $45. These are the very same units that many other companies modify and re-brand as their own. Hell AEM doesn't even remove the original MAC branding and just slaps on their own labels. This is the one that I am using currently and it is perfect.

The only after market BOV/BPV I like is Synapse Engineering. It is not cheap but it is worth the money and you need to purchase an adapter to use it as a BPV. It is the only one on the market that is actually designed to improve performance by bypassing the turbo during deceleration conditions and during idle thereby improving throttle response. Since it is synchronic it adapts itself to the entire range of performance from daily driving to full on race with little to no adjustments needed.

 

[Doppelganger]

I assume this is a stock turbo?

To be completely honest if it aint broke done fix. Meaning you will not see any noticeable gains from a BPV unless you have a reason to replace it. For a stock turbo the stock BPV is the absolute best. A BPV will not help you hold boost but may help you improve shifting if you get the right one and can adjust it to allow you to compensate for a variety of issues. For holding boost you would need to look into a larger turbo. The stock one runs out is team quickly and tapers regardless of how much you adjust boost control.

The same philosophy can be applied to the EBCS as well in that, if you are achieving boost targets then job done. The boost control system in the ECU is wildly capable of tailoring the boost curve for strategy tuning even with the stock EBCS. You just need to find a tuner that knows how to do it. The moment I would replace the stock EBCS is when you need more than 85% waste gate duty to achieve your target boost but even that is not absolute. The turbo itself could be the determining factor there.

As for brands I think pretty much all of them are overpriced toys at best. Especially when it comes to the EBCS. You could buy a MAC pneumatic valve from eBay complete with fittings, brackets and connectors for less than $45. These are the very same units that many other companies modify and re-brand as their own. Hell AEM doesn't even remove the original MAC branding and just slaps on their own labels. This is the one that I am using currently and it is perfect.

The only after market BOV/BPV I like is Synapse Engineering. It is not cheap but it is worth the money and you need to purchase an adapter to use it as a BPV. It is the only one on the market that is actually designed to improve performance by bypassing the turbo during deceleration conditions and during idle thereby improving throttle response. Since it is synchronic it adapts itself to the entire range of performance from daily driving to full on race with little to no adjustments needed.

Great response George. The synapse is the only BPV I'd replace mine with only if my stock BPV gives me issues in the tuning process.

I also only picked up a grim Speed boost controller due to the fact that I purchased it with a spare tire and jack for $50

Sent from my ONEPLUS A3000 using Tapatalk

 

[Piper86]

Great feedback thanks!
Yes I agree 100% with the if it ain't broken don't fix it philosophy which is why I'm only looking into these options for if it were to cone to this. You see I'm very finicky on what goes on and into my car so this is why I'm researching now for if the day comes I know what I want.

As the car is 10years old and I'm not sure if its the original BOV (its OEM but dint know where its from as the car used to have a GFB BOV which I had removed because I don't like the hissing and puffing it made).

Anyhow thanks for the great advice!

 

[Piper86]

Oh yes and you assumed correctly, standard turbo, vf43.

 

[SDMotorworks]

If you need any of the pars let us know, we have had customers use all of those brands of BPV and all really liked them. The Synapse is a good one which most people stay away from because of the price but its a good quality to go with. Let us know how we can help you.

 

[Piper86]

Had my car tuned with stock BOV and the car is running smooth.

So decided to stick with stock for now. However I will continue keeping an Eye open for something I like, but if it ain't broken I'm not changing it

Had a relook at parts and really like the HKS products. Just wish HKS had a full recirculation BPV.

Have decided to look into a HKS EVC 6 boost controller in future so that I can run a low and high boost map.

Where do you guys mount your BC controller screen? I was thinking inside the ash tray i. The centre console but still need to check if it would fig there and keep the 12v socket in tact as I make use of it.

 

[HolyCrapItsFast]

If I am not mistaken you can get an adapter for the HKS bov to use it as a bpv

 

[Piper86]

If I am not mistaken you can get an adapter for the HKS bov to use it as a bpv

Thanks a million, I was not aware of the suction return kit available on the HKS BOV's.
Thanks a lot.

http://www.hks-power.co.jp/en/product/blow_off/option/index.html

 

[Real Auto Dynamics]

Nice!

 

[STIGR-Wagon-Dad]

Synapse engineering Diverter valve. That's what I use. It improved my throttle response and boost recovery between gear shift.

 

[SDMotorworks]

[MENTION=5834]Piper86[/MENTION] let us know if you need the HKS stuff, we can get you what you need.