Questions about VTT Aluminum Outlet Testing Results

Rob@RBTurbo

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Great results, it is always awesome to see some positive delta in hi-po parts!!

As anyone who has studied the N54 turbocharger outlet tract may understand, the compressor housing outlet ID is actually quite small (~1") whereas the OE outlet tubing is quite a bit larger (~1.5"). For this reason BMW engineers designed a transitional adapter (which is integrated into the OE outlet assembly) to provide a "port matching taper" to transition the smaller ID (at the compressor housing outlet) to the larger ID (at the outlet tubing entrance)- to effectively increase airflow by reducing turbulence from the otherwise gaping mismatch of port sizing.

We have noticed on this aftermarket part the transitional adapter has been removed, which leads to a couple questions:
1) Any idea the impact of the outlet assembly flow increase that can be accredited to the removal of these transitional adapters?
2) Any idea the impact of removing the OE engineered transitional adapter from this connection from a functional system/turbulence perspective?

Appreciate the time.

Rob
 

doublespaces

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This thread was moved to the Octagon per the Vendor rules, please see Rule #4, Vendor threads are explicitly protected from detraction from the purpose set by the original poster. As a refresher, a Vendor thread, is a thread whose starter is a Vendor for a promotional purpose. You may continue your questions here and they may elect to respond.
 

Rob@RBTurbo

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This thread was moved to the Octagon per the Vendor rules, please see Rule #4, Vendor threads are explicitly protected from detraction from the purpose set by the original poster. As a refresher, a Vendor thread, is a thread whose starter is a Vendor for a promotional purpose. You may continue your questions here and they may elect to respond.

My bad. Didn't realize that was a violation of a rule and thought it was a reasonable question.
 

doublespaces

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In a normal thread, your response was appropriate. Vendor threads are protected from distraction by other vendors so the purpose of promoting can continue unimpeded. You may however ask any questions you have here, there are no rules in the octagon.
 
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Rob@RBTurbo

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In a normal thread, your response was appropriate. Vendor threads are protected from distraction by other vendors so the purpose of promoting can continue unimpeded. You may however ask any questions you have here, there are no rules in the octagon.

Seems as if the Octagon is right up there with the bermuda triangle, just a place for stuff to get lost. And to think we were really looking forward to those answers. Oh well.

Rob
 
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doublespaces

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Seems as if the Octagon is right up there with the bermuda triangle, just a place for stuff to get lost. And to think we were really looking forward to those answers. Oh well.

Rob

There is a direct link in that thread right to this one. If anyone cares they will follow it to here and they can demand a reply from anyone they want.
 
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dyezak

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Great results, it is always awesome to see some positive delta in hi-po parts!!

As anyone who has studied the N54 turbocharger outlet tract may understand, the compressor housing outlet ID is actually quite small (~1") whereas the OE outlet tubing is quite a bit larger (~1.5"). For this reason BMW engineers designed a transitional adapter (which is integrated into the OE outlet assembly) to provide a "port matching taper" to transition the smaller ID (at the compressor housing outlet) to the larger ID (at the outlet tubing entrance)- to effectively increase airflow by reducing turbulence from the otherwise gaping mismatch of port sizing.

We have noticed on this aftermarket part the transitional adapter has been removed, which leads to a couple questions:
1) Any idea the impact of the outlet assembly flow increase that can be accredited to the removal of these transitional adapters?
2) Any idea the impact of removing the OE engineered transitional adapter from this connection from a functional system/turbulence perspective?

Appreciate the time.

Rob

You are talking about the transition setup for the OE turbo outlet going into the OE pipe right. Correct me if I'm wrong, but VTT's GC series don't have that feature. They have a normal outlet, correct?
 

BreakMyBillfold

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It would be interesting to add transitional adapters into the compressor housing outlet, perhaps machined from take-off OEM outlets. They could perhaps be inserted into the housing outlet. Maybe bonded into place somehow if o-ring tension isn't enough to retain them.
 

Rob@RBTurbo

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It would be interesting to add transitional adapters into the compressor housing outlet, perhaps machined from take-off OEM outlets. They could perhaps be inserted into the housing outlet. Maybe bonded into place somehow if o-ring tension isn't enough to retain them.

If one wants to simply and effectively challenge the aftermarket outlet vs. the OEM outlet- the simplest function would be to just cut off the transitional adapters from the OEM outlet. This would be a very apples to apples comparison in testing the OEM vs. Aftermarket primary tubing/merger/etc.

But this is not what was done and of course the vendor in question here decided to leave the transitional adapters in place on the OEM pipe for why? Because they knew it would equate to a significant delta in the favor of their offering. It only takes a tiny bit of mechanical logic to understand that a 1" ID Transitional adapter is going to impede flow significantly from it's adjoining and otherwise much larger ~1.38" ID primary tubing.

The sad part (being that they have more than a tiny bit of mechanical logic) is they know this would play in the favor which is indeed very slimy, but not an unusual tactic for these guys to make a sale (and it will work as usual). And also as usual they will correct the products shortcomings over the next year or so and it'll be a "sorry for ya" for those poor saps who fell victim to the latest charade that could've easily been avoided. All we can say to the more intelligent types of the world (who will take the moment to listen and learn) is that it is a simple Buyer Beware of these types of marketers in the performance industry. As such we'd suggest keeping your OEM outlets until a solution comes about that you feel is designed with significant superiority over the OEM unit (ie. PSP).

Rob
 
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veer90

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It would be interesting to add transitional adapters into the compressor housing outlet, perhaps machined from take-off OEM outlets. They could perhaps be inserted into the housing outlet. Maybe bonded into place somehow if o-ring tension isn't enough to retain them.

Rob is literally grasping at straws because the results weren't in his favor, now he's trying to find any little thing to cry foul. Not to mention his posts are insultingly passive aggressive. He talks down like anyone who isn't him is total moron.

Also don't expect a response from him since he put me on ignore :tearsofjoy:
 

BreakMyBillfold

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If one wants to simply and effectively challenge the aftermarket outlet vs. the OEM outlet- the simplest function would be to just cut off the transitional adapters from the OEM outlet. This would be a very apples to apples comparison in testing the OEM vs. Aftermarket primary tubing/merger/etc.

But this is not what was done and of course the vendor in question here decided to leave the transitional adapters in place on the OEM pipe for why? Because they knew it would equate to a significant delta in the favor of their offering. It only takes a tiny bit of mechanical logic to understand that a 1" ID Transitional adapter is going to impede flow significantly from it's adjoining and otherwise much larger ~1.38" ID primary tubing.

The sad part (being that they have more than a tiny bit of mechanical logic) is they know this would play in the favor which is indeed very slimy, but not an unusual tactic for these guys to make a sale (and it will work as usual). And also as usual they will correct the products shortcomings over the next year or so and it'll be a "sorry for ya" for those poor saps who fell victim to the latest charade that could've easily been avoided. All we can say to the more intelligent types of the world (who will take the moment to listen and learn) is that it is a simple Buyer Beware of these types of marketers in the performance industry. As such we'd suggest keeping your OEM outlets until a solution comes about that you feel is designed with significant superiority over the OEM unit (ie. PSP).

Rob
What do you mean about leaving the transitional adapters in place on the OEM pipe? You mean during the flow testing? Wouldn't that make them more efficient rather than less, if they help the flow? Sort of like a velocity stack effect.

In lieu if the face-sealing v-band interface, I'd be interested in an aluminum outlet that was terminated with the OEM ends from the stock outlet, as long as the large side of the taper matched the I.D. of the outlet runner.
 

Rob@RBTurbo

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What do you mean about leaving the transitional adapters in place on the OEM pipe? You mean during the flow testing? Wouldn't that make them more efficient rather than less, if they help the flow? Sort of like a velocity stack effect.

In lieu if the face-sealing v-band interface, I'd be interested in an aluminum outlet that was terminated with the OEM ends from the stock outlet, as long as the large side of the taper matched the I.D. of the outlet runner.

Recap:

1) The transitional adapters left on the OEM outlet primary tubing (NOTE: ONLY during flow testing) would make the OEM outlet assembly flow significantly less- which from a marketing perspective makes an aftermarket unit that does NOT have transitional adapters in place seem as if it is a rather large improvement (even if it is not).

2) The transitional adapters left on the OEM outlet primary tubing (NOTE: Installed as a functional working system) would make the OEM outlet assembly flow better as it has smoother port matching from the compressor housing outlet to the primary outlet plumbing. (NOTE 2: Testing the importance of transitional adapter functionality vs. the lack thereof would require some more complexity in the test- and is not really the primary topic at hand but certainly a valid one nonetheless.)

The topic of priority was to point out that the Aftermarket outlet was poorly designed from a merger perspective, and equal to the OEM from a primary tubing perspective. So the aftermarket outlet is most likely at best equivalent to that of the OEM outlet when it comes to performance potential.

So there are two factors here and if you are a greasy marketer, you adjust testing accordingly to meet your needs and to wow the masses. In this case the marketer chose to leave the transitional adapters on the OEM pipe such that it's flow potential was reduced, leaving an appearance that the OEM outlet pipe has less performance potential than their aftermarket pipe. In short data (although conveniently provided) is not always reliable and can always been skewed.

Thanks,
Rob
 
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BreakMyBillfold

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Rob is literally grasping at straws because the results weren't in his favor, now he's trying to find any little thing to cry foul. Not to mention his posts are insultingly passive aggressive. He talks down like anyone who isn't him is total moron.

Also don't expect a response from him since he put me on ignore :tearsofjoy:
I think it's a fair point about the transition. As brilliant as I thought the face-sealing outlet adapters VTT designed for their silicone outlets were when I first saw them, I later saw the same point brought up and addressed by MMP in their version. The adapters for their silicone outlets mate to the compressor housing like stock and provide a version of a tapered transition.
 

Rob@RBTurbo

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I think it's a fair point about the transition. As brilliant as I thought the face-sealing outlet adapters VTT designed for their silicone outlets were when I first saw them, I later saw the same point brought up and addressed by MMP in their version. The adapters for their silicone outlets mate to the compressor housing like stock and provide a version of a tapered transition.

There is zero doubt that transitional adapters are important where warranted- such as where adjoining ports do not match in sizing (which in this instance is rather severe). Unfortunately in this case these adapters were of all things used against the OEM pipe when tested on a bench vs. the aftermarket pipe, which was non-disclosed of course and then the acquired data plastered all over the forums without further care. Just take note and understand that "data", although cool sometimes, is not always what it seems and can be very simply manipulated to meet the needs of an unscrupulous vendor.

Thanks,
Rob
 
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BreakMyBillfold

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Recap:

1) The transitional adapters left on the OEM outlet primary tubing (NOTE: ONLY during flow testing) would make the OEM outlet assembly flow significantly less- which from a marketing perspective makes an aftermarket unit that does NOT have transitional adapters in place seem as if it is a rather large improvement (even if it is not).

2) The transitional adapters left on the OEM outlet primary tubing (NOTE: Installed as a functional working system) would make the OEM outlet assembly flow better as it has smoother port matching from the compressor housing outlet to the primary outlet plumbing. (NOTE 2: Testing the importance of transitional adapter functionality vs. the lack thereof would require some more complexity in the test- and is not really the primary topic at hand but certainly a valid one nonetheless.)

The topic of priority was to point out that the Aftermarket outlet was poorly designed from a merger perspective, and equal to the OEM from a primary tubing perspective. So the aftermarket outlet is most likely at best equivalent to that of the OEM outlet when it comes to performance potential.

So there are two factors here and if you are a greasy marketer, you adjust testing accordingly to meet your needs and to wow the masses. In this case the marketer chose to leave the transitional adapters on the OEM pipe such that it's flow potential was reduced, leaving an appearance that the OEM outlet pipe has less performance potential than their aftermarket pipe. In short data (although conveniently provided) is not always reliable and can always been skewed.

Thanks,
Rob
In other words, if both set ups were tested with say a cut off compressor housing outlet v-banded to each setup to be closer to the installed configuration, it would be a more meaningful/less skewed test. To make it equal the same compressor outlet "stubs" could be used in both tests.

This could be a more direct comparison, going from open air in the testing room, through the compressor stubs, expanding smoothly in the OEM outlets, and expanding turbulently in the stepped VTT outlets.

The tests could even be filmed in landscape mode. :wink:
 

Rob@RBTurbo

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In other words, if both set ups were tested with say a cut off compressor housing outlet v-banded to each setup to be closer to the installed configuration, it would be a more meaningful/less skewed test. To make it equal the same compressor outlet "stubs" could be used in both tests.

This could be a more direct comparison, going from open air in the testing room, through the compressor stubs, expanding smoothly in the OEM outlets, and expanding turbulently in the stepped VTT outlets.

The tests could even be filmed in landscape mode. :wink:

Looks like we have one who actually gets some basic principles of performance, welcome to the internet you have been missed... you are a dying breed sir.:sunglasses:

You are 100% correct that IF they were to cut off the same OE compressor housings (ie. 4 front housings at the exact same points) and then V-band altogether, it would be the perfect test environment for comparing the OE Outlet package to the Aftermarket Outlet package.

Unfortunately we wouldn't put it past these guys to "port out" the 2 cut off housing ends that would be installed on their aftermarket outlet, to in essence attempt to further match their straight cut adapter in order to get the same/similar results. Plus they'd have to destroy 4 housings which is a lot more to ask than to simply destroy one OEM outlet. This said it also would be effective to cut off the OE transition ends and re-test accordingly- however indeed this would leave out the entire picture and really only compare the actual outlet plumbing (primary tubing/merger) flow characteristics in themselves.

Keep in mind the vendor spokesman (who typically seems a bit more honest) is in another state from the actual vendor (who is quite corrupt in his business dealings); so more often that not you can not put much merit into their "combined" end results.

Rob
 
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BreakMyBillfold

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You are 100% correct that IF they were to cut off the same OE compressor housings (ie. 4 front housings at the exact same points) and then V-band altogether, it would be the perfect test environment for comparing the OE Outlet package to the Aftermarket Outlet package.
In my envisioned scenario, since there would be only one flow bench and each outlet would need to be set up, the same two compressor stubs would be used on each outlet.

If the setting up is included in the "one take" uneditted sequence, the stubs can be shown closely before/after/before/after to allay potential concerns about shenanigans.

This is hypothetical, of course.

I have a set of uninstalled MMP silicone outlets. I suppose I could I assume the actual piping flowed better than the dented OEM version, and chop off the v-band ends and attach the MMP adapters with short hoses. Or chop up the OEM outlet to harvest the transitions to stick in there.

Damn phone autocorrect and even auto post...
 
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Dusty Waterfall

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