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Discussion Starter · #1 ·
I just installed a BSR optiflow on my 2.8 v6. When I got over 3000 rpm and let go the gas pedal, I hear some kind of air blowing off sound. Is that normal? Everytime when I release the gas pedal in hig rpms, I will hear this air sound. What it is? Thanks!!
 

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Its your bypass valve working!!! You will hear your turbo spool up much more now and also the bypass valve.

I have the optiflow for the 2.0T and i get the same effect.

Enjoy it!
 

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Aeroist said:
I just installed a BSR optiflow on my 2.8 v6. When I got over 3000 rpm and let go the gas pedal, I hear some kind of air blowing off sound. Is that normal? Everytime when I release the gas pedal in hig rpms, I will hear this air sound. What it is? Thanks!!
Well thats pretty much what you bought it for; the sound! Very minimal performance gains, if any. Enjoy :cheesy:
 

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Aeroist said:
I just installed a BSR optiflow on my 2.8 v6. When I got over 3000 rpm and let go the gas pedal, I hear some kind of air blowing off sound. Is that normal? Everytime when I release the gas pedal in hig rpms, I will hear this air sound. What it is? Thanks!!
is your car black? i drove by the metreon yesterday and saw a black 2.8T with a bsr emblem on the right of the trunk.
 

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Actually full intakes on those 2.8Ts should yeild about 10 WHP. Although I don't know what the optiflow looks like, custom intakes Ive seen on most GM vehicles over 240 horse provides ~ 10WHP +

Shrug. Dyno it.
 

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Turbeau said:
Actually full intakes on those 2.8Ts should yield about 10 WHP.

Dyno it.
Not according to BSR or Hirsch. BSR claim no power gains for the Optiflow even up to Stage 3. Hirsch does not sell intakes because they "are interested in real power modifications."

At least these companies are up front about what they are selling or not selling. Other companies make big claims but post no dyno data.

EDIT: Ahh. Here's the pertinent thread:
http://www.saabcentral.com/forums/showthread.php?t=112149&highlight=intakes
 

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Hrm, they must not have really designed for power in mind. Shrug. I've never seen removal of a air box that didn't yeild power gains. Again, I don't know what the whole intake looks like. Got a link? It could just be like an inlet snorkle in which case they are right, it would be a zero horse gain.

hehe.

Ok so apparently on these vehicles, the maf is very close to the filter which leaves little of the intake to change.. Makes sense.

So what you could do is, put the maf closer to the turbo inlet ( not too close ) and change out the piping before it. There is your 3 inch intake which will free up some horse even though it probably drops to 2.5 inch by the time it gets to the turbo.

Or better yet, don't agree with what they are saying about tens of thousands of dollars to calibrate the MAF ( which is retarded because Ive done it in 40 minutes, its actually more of a constant... ) I've even changed it around and once went from draw through to blow through, and not had a problem...

So the only issue is you would need a tuner for the maf. Which i'll bring up in another thread.
 

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Turbeau said:
Hrm, they must not have really designed for power in mind. Shrug. I've never seen removal of a air box that didn't yeild power gains. Again, I don't know what the whole intake looks like. Got a link? It could just be like an inlet snorkle in which case they are right, it would be a zero horse gain.
Here's the link to my post with a pic after I installed the Opti Flow and 3 pt. brace: http://www.saabcentral.com/forums/showthread.php?t=112393
 

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Or it could just be that the stock airbox dosn't offer a sizable flow restriction that the sytem can't make up in another fashion. Remember that this is a completely dive by wire system (somewhere there is a great thread with feedback from the BSR rep that talks about this a bit). The 'gas' peddle is converted to a torque request, the computer decides how much gas and fuel are needed to meet this torque request with the air portion getting measured from the MAF. Simply put the only way a aftermarket intake is going to get you a net increase in HP is if the ECU was requesting more air than the engine/turbo are able to pull in. Simply put the stock intake isn't the restriction here. It is able to pull in plenty of air past the MAF to meet the requested air load. Changing the intake isn't going to to make the ECU request more air.
Only possible effect is is that you could get some improved throttle response because it will be easier for the engine/turbo get get up to the requested air load. So you might see a slight reduction in turbo lag and your tubro will probably isn't have to work as hard (but not a big difference here I am sure). Put another way, changing the intake isn't going to make the ECU decide that since it can easily get the requested air easier that is is going to increase the max tourque request. To do that you have to tune the ECU which is exactly what BSR does. They basicly teach the ECU higher air fuel loads that will allow for larger torque request.

At least that is my humble understanding of how the system works.

Edit: Found the link to old post. It is in the speed limitor post. http://www.saabcentral.com/forums/showpost.php?p=1071810&postcount=76
Turbeau said:
Hrm, they must not have really designed for power in mind. Shrug. I've never seen removal of a air box that didn't yeild power gains. Again, I don't know what the whole intake looks like. Got a link? It could just be like an inlet snorkle in which case they are right, it would be a zero horse gain.

hehe.

Ok so apparently on these vehicles, the maf is very close to the filter which leaves little of the intake to change.. Makes sense.

So what you could do is, put the maf closer to the turbo inlet ( not too close ) and change out the piping before it. There is your 3 inch intake which will free up some horse even though it probably drops to 2.5 inch by the time it gets to the turbo.

Or better yet, don't agree with what they are saying about tens of thousands of dollars to calibrate the MAF ( which is retarded because Ive done it in 40 minutes, its actually more of a constant... ) I've even changed it around and once went from draw through to blow through, and not had a problem...

So the only issue is you would need a tuner for the maf. Which i'll bring up in another thread.
 

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Turbeau said:
Or better yet, don't agree with what they are saying about tens of thousands of dollars to calibrate the MAF ( which is retarded because I've done it in 40 minutes, it's actually more of a constant... ) I've even changed it around and once went from draw through to blow through, and not had a problem...

So the only issue is you would need a tuner for the maf. Which i'll bring up in another thread.
I would like to see what you have done previously.

Every airflow graph I've seen shows a curve. The flow does not change proportionally over the rpm range or you would have a straight line with a slope, not a curve. This would simplify things tremendously, but it's not the case.
 

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Nah fish, your right about how the Med 9 works, I HATE drive by wire. Its a POS for my tastes.

On the Solstices (which uses the same Med9.x) they have problems with getting mods to yeild any long term benefit, because of that torque request.

However, again you can use a tuner to get another this which I am going to be posting about shortly.

The only effect the soltice owners seem to have on power on a permenant basis is an intercooler swap. Its weird though, some have luck making power others dont. Those that are tuned don't have an issue though.\


ctrl, well yeah it is somewhat of a curve, but its not very difficult you only really need to do is find the area change, and convert it into a constant you want to use, and you really only need to deviate maybe 15% at most to dial it in.
What I had to do with my MAF swap was, I didn't change the piping diameter, I just changed the MAF sensor ( but mind you the MAF sensor was contained in a ABS which was a different size than the stock one. So effectively the diameter really did change just not the charge piping...

The real issue here is what fish stated about the torque requested proceedure for the MEDs.

Unless tuned making the motor more efficent will do little more than just ask the vehicle to open less of the throttle, or dial back the boost. Don't get me wrong it MIGHT yeild a power increase, but not as expected.
 

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Discussion Starter · #12 ·
soul05 said:
is your car black? i drove by the metreon yesterday and saw a black 2.8T with a bsr emblem on the right of the trunk.
That's not me, but my car is black though. You know it's me if you see a black one with a black mesh grille. I think I saw the car you mentioned above before. It's pretty nice.
 
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