Boost spiking/High

[Edkiefer]

Hi guys, don't have EB but from your graphs were is the boost in your graphs being read from ?
I ask cause were you should see most delta with a BV is from the intercooler output(before TB) to IM (after TB).
If the BV was faulty, not working you should gets spikes when you let off throttle in the hot side pipe but the IM shouldn't be affective to much as I "think" throttle closes as one of safety features (anyone correct me as again never tuned one).

Anyway, if say you wen 3rd gear pull with relative slow throttle to WOT and let throttle off very slow, if boost is still very high (during the pull mid way) then IMO its not BV, but WG, at least on stock car.

Of course replacing the BV is simple mater to test it out.

Are you using the extra spring ( I saw one BV+ and there was optional spring) maybe try removing it if you do see spikes going away or better talk to manufacture, maybe he is not aware of this issue.

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[Marvinmadman]

Intake manifold MAP sensor should be the boost source.

 

[ForYourOwnGood]

That was my guess, the DV+ may be the cause of the spike to 30psi when you let off. The 26 psi steady boost may be the WGA or as you said, maybe a leak?

Not necessarily. We know already that these cars will go into overboost condition by closing the throttle under other circumstances (for example, trying to run a catless downpipe on the stock tune), since everything is computer controlled and not vacuum controlled like on a classic turbo car, something the DV+ is doing may be causing to computer to respond by closing the throttle and raising boost even higher.

This would be in line with the weird symptom I've been having where at part throttle I make a lot of boost but get almost no acceleration.

 

[ForYourOwnGood]

Alright, quick update. I did several 3rd and 4th gear pulls on the way to work with the stock BPV in. Car holds 22psi no problem and pulls way harder than before. I might try the DV+ with no spring in a few days when I have time to swap it again and see how that does, but I'm fairly certain that is the culprit in my case now. I'm not sure how it is effecting the management system but its obviously doing something, throttle response is night and day better now too (like it was when I first but the DV+ in).

Best guess is, like the Forge unit I had on my mazda the spring is trying to rotate and binding up causing the piston to not move at all when commanded, and the car is likely closing the throttle plate in response to the overboost condition, I remember Adam from Tune+ saying it will do that.

 

[Edkiefer]

Alright, quick update. I did several 3rd and 4th gear pulls on the way to work with the stock BPV in. Car holds 22psi no problem and pulls way harder than before. I might try the DV+ with no spring in a few days when I have time to swap it again and see how that does, but I'm fairly certain that is the culprit in my case now. I'm not sure how it is effecting the management system but its obviously doing something, throttle response is night and day better now too (like it was when I first but the DV+ in).

Best guess is, like the Forge unit I had on my mazda the spring is trying to rotate and binding up causing the piston to not move at all when commanded, and the car is likely closing the throttle plate in response to the overboost condition, I remember Adam from Tune+ saying it will do that.

Yeh, I would try it w/o spring, but if your right that spring is binding , a fix would be adding a thrust bearing to end of spring end (spring would need shorting the thickness of bearing, but there pretty thin).

If you could map the map boost pressure with TB TPS values, that would show if TB is being closed by ECU and when boost spike with throttle angle.

 

[arghx7]

Your car is stock. Why don't you trust that the Ford engineers knew what they were doing when they designed the whole system, including the stock BOV?

Stock tune, stock parts - car runs fine
Stock tune, stock parts except that one you changed out with dubious marketing claims - car runs bad

 

[ForYourOwnGood]

Your car is stock. Why don't you trust that the Ford engineers knew what they were doing when they designed the whole system, including the stock BOV?

Stock tune, stock parts - car runs fine
Stock tune, stock parts except that one you changed out with dubious marketing claims - car runs bad

1) My car isn't stock.
2) Engineers design within the specified budget and save cost wherever they can (case in point, the garbage intercooler). There is always room for improvement. My plastic junk BPV is cracked almost in half and leaks like crazy.

 

[Spykexx]

Your car is stock. Why don't you trust that the Ford engineers knew what they were doing when they designed the whole system, including the stock BOV?

Stock tune, stock parts - car runs fine
Stock tune, stock parts except that one you changed out with dubious marketing claims - car runs bad

That's laughable at best. If this was the case there would be no aftermarket. As stated by [MENTION=25032]ForYourOwnGood[/MENTION], the intercooler is a great example. It's absolute garbage. Why didn't they include a DV catch can? Why did they leave a ridiculous amount of power on the table, but will be utilizing it in 2018 refresh with overboost? Why did they use a DV that leaks like crazy even brand new?

You seem to think that the DV+ replaces the entire DV. It's just an upgraded piston for the stock DV. Tear your DV apart and look at the piston. It's a joke. Flimsy little plastic piston with holes in it.

[MENTION=25032]ForYourOwnGood[/MENTION] I'm kinda wanting to try out not using that hard inner spring. DV+ states it should run more more "like factory" that way.

 

[ForYourOwnGood]

[MENTION=25032]ForYourOwnGood[/MENTION] I'm kinda wanting to try out not using that hard inner spring. DV+ states it should run more more "like factory" that way.

Yeah I'm going to put mine in that way tomorrow morning. I'll let you know how it goes.

 

[jbailer]

Can you guys help me with the use of the spring? I purchased the DV+ but haven't installed it. Is the use of the spring optional? What is the benefit or negative from using it? To be honest, I haven't installed it yet because I haven't seen an issue. Mine holds at about 22.5 psi pretty steady.

 

[ForYourOwnGood]

Can you guys help me with the use of the spring? I purchased the DV+ but haven't installed it. Is the use of the spring optional? What is the benefit or negative from using it? To be honest, I haven't installed it yet because I haven't seen an issue. Mine holds at about 22.5 psi pretty steady.

Spring is optional. I'll put mine in without the spring and give an update on how it feels. My stock BPV hold 22psi until around 5000rpm and then tapers off badly.

 

[Spykexx]

Can you guys help me with the use of the spring? I purchased the DV+ but haven't installed it. Is the use of the spring optional? What is the benefit or negative from using it? To be honest, I haven't installed it yet because I haven't seen an issue. Mine holds at about 22.5 psi pretty steady.

Yes it's optional. The spring just allows for the inner piston to seat harder against the copper piston. If you leave it out GFB states it'll recover on shift just like stock with the benefit of a copper piston over plastic.

Direct from the instructions from GFB

The DV+ can be configured in two different ways, depending on your desired outcome. Fitting the DV+
with the main spring installed as shown on the previous page can be thought of as a “Sport” mode,
offering the best possible throttle response and boost recovery during on/off throttle applications (i.e.
during gearshift with a manual transmission).
Using the main spring means the DV+ can open and close progressively in response to how much boost
pressure is present, unlike the factory diverter which just opens fully regardless of whether there is boost
to vent or not. Because this operation method is different from the factory diverter, it is not unusual (or
detrimental) to hear a different sound from the intake when lifting off the throttle at low RPM, especially
if you have an aftermarket intake or a larger turbo installed.
If a different sound does occur and bothers you, it is possible to install the DV+ WITHOUT the main spring
behind the piston. This configuration can be thought of as an improved “Standard” mode, which behaves
just like the factory diverter, but with the added benefits of better boost-holding, strength, and reliability.

 

[jbailer]

Spring is optional. I'll put mine in without the spring and give an update on how it feels. My stock BPV hold 22psi until around 5000rpm and then tapers off badly.

I have the Ford Performance tune, maybe that's the difference for me? So why would I use the spring or choose to not use it? What does it do? This is a datalog I did and shared in another thread.

 

[Spykexx]

I have the Ford Performance tune, maybe that's the difference for me? So why would I use the spring or choose to not use it? What does it do? This is a datalog I did and shared in another thread.

Well this brings on some curiosity. How are you losing only 2 PSI through shifts? No lift shifting? Lol.

But take a good look at how "choppy" your boost line is. Constantly moving between 22.5 and 20. Looks like you're leaking to me! Look at third gear. Constantly losing and gaining boost. The stocker doesn't do a good job of holding high boost, it's flimsy plastic (I was amazed when I seen the piston they used).

Look at the smoothness of my boost (Even when it gets a little rough, it's only gaining boost, not losing). Compare it to how your boost is.

Without the spring it'll shift much more like stock, but hold your boost at higher pressure than the stock DV will. IE smoother boost. With the spring it retains more pressure upon shifting.

 

[jbailer]

Well this brings on some curiosity. How are you losing only 2 PSI through shifts? No lift shifting? Lol.

No lifting because it's an automatic. I wouldn't say I'm losing 2psi through shifting either because it doesn't drop at the shift, it is just constantly bobbling between 20 - 22.5.

But take a good look at how "choppy" your boost line is. Constantly moving between 22.5 and 20. Looks like you're leaking to me! Look at third gear. Constantly losing and gaining boost. The stocker doesn't do a good job of holding high boost, it's flimsy plastic (I was amazed when I seen the piston they used).

Look at the smoothness of my boost (Even when it gets a little rough, it's only gaining boost, not losing). Compare it to how your boost is.

That's good feedback. I'm a turbo noob and not really sure what to expect. I'm very familiar with superchargers and would expect that to be much smoother or I would be looking for belt slip, maybe a tensioner issue. With the turbo, I didn't know it should be smoother. For all I knew it might be a normal process of the ECU trying to manage the boost level and the 2.5psi was considered very good.

Without the spring it'll shift much more like stock, but hold your boost at higher pressure than the stock DV will. IE smoother boost. With the spring it retains more pressure upon shifting.

I'm not sure I understand that correctly. Are you saying the spring will just help hold the boost during shifts and without the spring it will be much like the stock BPV just not leak and should be holding at a steady 22.5psi in my case? If so, then in my case, it seems the no spring option would be best since I'm not losing boost during shift.

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