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      08-23-2011, 01:07 PM   #23
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Quote:
Originally Posted by Papethova View Post
So why couldnt you have one twin scroll on each bank of 3? twinbiturbo?
because that would be 4 turbos feeding 6 cylinders. Its a fraction that needs to be able to be reduced to an integer.

The plumbing doesnt work.
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      08-23-2011, 02:55 PM   #24
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Quote:
Originally Posted by adrean8j View Post
^^^In American english a bi-turbo would be sequential instead of parallel or "twin" turbos.....kinda like Siamese twins versus actual separate identical twins (in that Siamese twins share some "piping"...LOL)
really? For me a bi or twin turbo mean exactly the same, meaning two turbo's. Nothing more, nothing less. Some brands have a bi-turbo, where the turbo's are identical size. Sequential or parallel is what I know not related to the wording bi or twin turbo.

I just googled it, even in WIKI they explain bi and twin turbo as the same.
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      08-23-2011, 02:57 PM   #25
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Quote:
Originally Posted by BrokenVert View Post
because that would be 4 turbos feeding 6 cylinders. Its a fraction that needs to be able to be reduced to an integer.

The plumbing doesnt work.
exactly. 2 twin scroll need a multiple of 4 cylinders.

Last edited by marcel b; 08-24-2011 at 02:26 AM..
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      08-23-2011, 05:56 PM   #26
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Quote:
Originally Posted by BrokenVert View Post
because that would be 4 turbos feeding 6 cylinders. Its a fraction that needs to be able to be reduced to an integer.

The plumbing doesnt work.
Thanks I thought sequential was in line
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      08-23-2011, 06:47 PM   #27
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Quote:
Originally Posted by marcel b View Post
exactly. s twin scroll need a multiple of 4 cylinders.
Close. Multiple of 2

#grammarnazi

Quote:
Originally Posted by Papethova View Post
Thanks I thought sequential was in line
it does. But that's on the exhaust end of it. On the intake stream you need to be able to have an integer inorder to provide even airflow to all cylinders
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      08-24-2011, 02:27 AM   #28
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Quote:
Originally Posted by BrokenVert View Post
Close. Multiple of 2
typing error... I meant 2 twin scroll turbo's
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      08-24-2011, 07:48 AM   #29
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Quote:
Originally Posted by BrokenVert View Post
A biturbo arraignment has two different sized turbos (usually a small one for low engine speed and a large one for the upper range) that share the same exhaust piping so they are known as sequential, because the large one is downstream of the small one (several BMW diesels are bi turbos)

This is similar to the idea of a twin scroll turbo like on the N55, but bot quite as both the small and large turbo impellers share the same housing in a twinscroll. Think of a twinscroll as a tightly packaged Bi Turbo

A twin turbo has two identical turbos that get fed off of two different headers. Twin turbos on a 6 are two banks of 3 cylinders, twins on an 8 pot are two banks of 4 cylinders, etc...

And you can't simply swap turbos on the N54. The turbo housings are cast into the header. So you Either need a custom header made or the second, easier option, which is to put a more efficient turbo possible into the stock housing (this is what ASR and RB do)

But again do not give money to ASR! They are thieves!
This is also wrong. A twinscroll turbo does not have two sets of impellers embedded in the a single housing. It separates the exhaust flow into two so the pulses generated by the cylinders don't cancel each other out.

Lots of misinformation in this thread.
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      08-24-2011, 08:00 AM   #30
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"both the small and large turbo impellers share the same housing in a twinscroll" - that's the most entertaining wrongness I've read in a long time
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      08-24-2011, 08:24 AM   #31
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Quote:
Originally Posted by ZCP M3 View Post
Lots of misinformation in this thread.
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Originally Posted by clived View Post
"both the small and large turbo impellers share the same housing in a twinscroll" - that's the most entertaining wrongness I've read in a long time
LOL...make sure you guys correct all that wrongness with truthiness when you post! Don't just say its wrong
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      08-24-2011, 08:30 AM   #32
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I'd have just have been repeating ZCP's explaination adrean...
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      08-24-2011, 08:32 AM   #33
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Quote:
Originally Posted by clived View Post
"both the small and large turbo impellers share the same housing in a twinscroll" - that's the most entertaining wrongness I've read in a long time
It's a turbo within a turbo within a turbo

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      08-24-2011, 08:38 AM   #34
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Quote:
Originally Posted by ZCP M3 View Post
It's a turbo within a turbo within a turbo

Only if it spins forever...
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      08-24-2011, 08:43 AM   #35
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Originally Posted by clived View Post
I'd have just have been repeating ZCP's explaination adrean...
I understand...it was more of a general statement.
Been lots of times I have seen others complain that someone is wrong and NOT have the facts or good details to back up why it is that way. No worries mate!
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      08-24-2011, 09:53 AM   #36
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Haha you guys are too much. Ok I'll give you that one I'm wrong. It doesn't happen that often tho, so you get the win

Tho I was doing this for a while before posting that.


I always wondered how it would work with my explanation.
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      08-24-2011, 10:06 AM   #37
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Quote:
Originally Posted by BrokenVert View Post
Haha you guys are too much. Ok I'll give you that one I'm wrong. It doesn't happen that often tho, so you get the win

Tho I was doing this for a while before posting that.

I always wondered how it would work with my explanation.
Thanks, now we know to ignore anything you post regarding turbos.
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      08-24-2011, 10:07 AM   #38
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Quote:
Originally Posted by bdaddylo View Post
Thanks, now we know to ignore anything you post regarding turbos.
No the rest of it is right. I was just off base regarding twin scrolls. Which ha nothing to do with this topic anyway.
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