V
What does a blow off valve do on paper?
- Thread starter Driver_88
- Start date
GTI2007 said:
The Forge BOV is NOT a valve at all,...it is a spacer that attaches to the OEM valve that makes noise ONLY. No gains at all.
In other turbo engines which are tuned to actually use bov's, a properly utilized and tuned bov can prevent the loss of power by reducing lost boost pressure under load, and operating quickly and efficiently during throttle/shift transitions, maintaining turbine speed, and protecting the throttle valve(s).
MHS216
Anchors Aweigh
- Location
- All over the place...
- Car(s)
- UG GTI 2006
GTI2007 said:
No, when you get the Forge SPACER, it spaces the distance the air has to travel through the Diverter Valve. This is how it is able to get the "Whoosh" noise. Think about blowing a whistle, it is almost exactly the same concept. You use the same stock diverter valve when using the spacer.
There is no Blow-off valve for this engine, just a diverter-valve spacer.
I've said this in a couple other posts, but I'll reiterate it here. I had a Forge spacer on my car for about 3 weeks and drove about 1000miles with it. First of all the sound gets really old. It happens every time you decrease throttle at all. Even when you think about letting off the gas it seems to blow off. This may happen just driving normally, it may be when shifting, either way it happens A LOT!!! I decided to take it off because of this reason.
After taking the valve off, I went for a quick drive. The car was noticeably quicker stock. Shifting was smoother too as not as much power was lost engaging the clutch. I was blown away with how much power was lost. I didn't expect any gains in power, but I didn't expect to lose any either.
If you think about it from an engineering standpoint the car is designed to use a diverter valve. This means that some of the unused boost will be returned to the intake, and the car is expecting this to happen at a certain rate depending on boost PSI. When you send some of that boost out into the atmosphere, the car is losing some of the boost that it is expecting to use again. Now I don't fully understand the functions of the cars ECU, but I would think that it would be a little confused when that boost just disapears rather than be returned to the intake. This is why I think the car loses power. It is not getting the same amount of boost as it is supposed to, and the turbo is not constanly spooling at the rate it is supposed to in order to reduce turbo lag.
This is all just my little input since I've owned the product and used it for a good amount of time. I don't have any dyno number to prove, nor do I have any A/F readings. However, my butt dyno tells me that power was being lost. How much power? not much, but enough that once I took the spacer off my car felt faster and smoother.
RedlineMotorworks
Go Kart Champion
- Location
- Redline Motorworks
- Car(s)
- 2007 BMP GTI
is it proven that the diverter valve actually decreases power?
I like my power, but I would like the louder sound...
I like my power, but I would like the louder sound...
Accel
Rally Car Champion
- Location
- Chino Hills, CA
I had no noticable loss in power.
07_BM_GTI said:
You really need to understand a mod before just slapping it on.
You are not understanding whats going on,.....the DV is actually an electro-solenoid controlled by the ECU. It's NOT like the 1.8t that is both vac and ecu influenced(you could alter retained boost with different DV springs). The 2.0t FSI DV can't be altered yet(other than via the ECU-maybe).
Regardless, the DV(or BOV) is not a performance altering component,...it is merely a valve to allow unused boost pressure to escape the system, protecting the throttle body, and allowing the turbine to remain spooled up.
In high power turbo applications a quality BOV(or DV), is required because of the increased airflow and boost involved. Almost any atmospheric valve(bov) will make the sound, but some makers have designed the sound to be even louder(HKS SSQ for example). Sound is a byproduct of the boost power involved, not the other way around.
As for the 2.0t, the stock DV works just fine.
The Forge SPACER vents a small portion(not all) of the DIVERTED air into the atmosphere which creates the sound. Some of that air is recirculated back into the intake side of the system. The air vented by the spacer MIGHT cause an alteration to the fuel trims of the 2.0t, but we are talking very MINOR adjustments made by the ECU to keep things in check. You should NOT experience any significant gains, or losses in power due to these adjustments. However, as you can read, many people have stated gains as high as 15hp and losses significant enough to be felt while driving.
You want the sound? Just buy the part already.
RedlineMotorworks
Go Kart Champion
- Location
- Redline Motorworks
- Car(s)
- 2007 BMP GTI
so in summary, the forge spacer has a larger gap for air to escape making a louder noise vs the small stock gap making a softer sound...performance won't change and if it does, you won't be able to notice it anyways
MHS216
Anchors Aweigh
- Location
- All over the place...
- Car(s)
- UG GTI 2006
DiscoGLI said:
I guess I was on crack every single time I drove my car for a 3 week period.:iono:
RedlineMotorworks
Go Kart Champion
- Location
- Redline Motorworks
- Car(s)
- 2007 BMP GTI
MHS216 said:
what..you noticed a loss in power?
MHS216
Anchors Aweigh
- Location
- All over the place...
- Car(s)
- UG GTI 2006
07_BM_GTI said:
Yes and No. As I said above, I didn't so much notice a loss in power when I was driving with the spacer. It was when I took the spacer off that I noticed a little quicker response and power, and in general smoother shifting. The car would have a little more power, stock when upshifting. I gather that this is because the extra boost is there to keep the turbo spooling and prevent lag, rather than being thrown out into the atmosphere.
While there is a debate that power may or may not be lost, the argument of gaining power is rediculous. There is just no way. Others on VW vortex have noticed a loss in power as well.
It's not catastrophic power loss, I just don't wanna have any part on my car that even maybe decreases power or that I question.
MHS216
Anchors Aweigh
- Location
- All over the place...
- Car(s)
- UG GTI 2006
DiscoGLI said:
And back to this....The info was provided by the company that makes the part, Forge MS. The car that they dyno'd also is chipped, and has a full TB Exhaust. Now they say that no power is lost, all they are doing though is 3 dyno pulls with a modified car.
Even if the spacer loses say 5hp at the crank, that is going to be offset by the gains of the chip and exhaust. There would be no possible way unless they dyno'd that smae exact car with the same mods, minus the Forge Spacer.
See how it's kinda fishy? Not trying to be a Dick, just trying to be a questioning consumer.
WEWO
Go Kart Newbie
- Location
- miami lakes
where can i get this spacer and how much does it cost??
MHS216
Anchors Aweigh
- Location
- All over the place...
- Car(s)
- UG GTI 2006
WEWO said:
Forge motorsports, north american motorsports. I bought mine directly from forge for $79 shipped if I remember correctly. Mine is for sale as well. Send me a PM.