That essentially sums it up. Each exhaust pulse is able to travel independently through it's own bank/runner. Because of this, one exhaust pulse will scavenge the exhaust out of the following combustion chamber once the exhaust valve opens...allowing more air to enter it on the next compression cycle. More air in = more power. There is simply no exhaust interference between exhaust pulses, allowing for a very efficient flowing system.

As I was writing my response, it dawned on me where I was becoming confused. I'll explain it below for those curious.

All of this stems from a natural occurring issue, Exhaust/Intake Valve overlap.

Had this been a twin Twin-Scroll Turbo setup, the Twin-Scroll Turbos would fare no better then standard Single-Scroll Turbos. This is because by the simple nature of the V6 arrangement and using 2 separate exhaust manifolds to feed each Turbo completely independent of the other bank.

...............................................Time: --------------->

Turbo 1 / Scroll 1 would see Cylinders: 1-NP-3-NP-5

Turbo 2 / Scroll 1 would see Cylinders: ....2-NP-4-NP-6

(NP = No pulse)

The above is ideal, as it provides that necessary time to avoid that brief negative pressure window (through valve overlap), introduced into the exhaust manifold impacting the next flow/pulse that is set to come out. This happens because the Cylinder pulses are spread out, from a time perspective, as they occupy different exhaust manifolds. This design allows for better scavenging and better exhaust efficiency.

__________________________________________________


The below is the most unideal scenario involving a single Single-Scroll Turbo and using a single exhaust manifold to collect all gasses and push them through said Turbo. Had Sasha not selected a Twin-Scroll Turbo, this is what our scenario would be.

...............................................Time: -------------->

Turbo 1 / Scroll 1 would see Cylinders: 1-2-3-4-5-6

The problem here is while Cylinder 2 is pushing out it's exhaust gases, Cylinder 1 very briefly introduced negative pressure in the exhaust manifold which slows gasses from Cylinder 2 down, which reduces scavenging effectiveness and Turbo efficiency. Repeat this many times over and suddenly you've reduced your Turbo's efficiency quite a bit.

__________________________________________________


The solution is a Twin-Scroll Turbo to 'mimic' a traditional twin Single-Scroll Turbo setup. This is what the Boosted Performance Turbo kit is. Even though both exhaust manifolds go to the same Turbo, they are kept separated throughout... until they finally meet at the Turbine when exiting the Turbo.

Thus you have:

...............................................Time: -------------->

Turbo 1 / Scroll 1 would see Cylinders: 1-NP-3-NP-5

Turbo 1 / Scroll 2 would see Cylinders: ....2-NP-4-NP-6

Even though the above is actually just one Turbo.

Look familiar? ;) ^^^


Hope this clears it up for others that were wondering. :)

Cheers,
MoulaZ

Also yes, BMW went from a twin Single-Scroll to a single Twin-Scroll setup from N54 to N55 in '09.

Technically as far as the engine is concerned, nothing changed. The exhaust of the Inline 6 engine was still split into 2 channels, 3 Cylinders each, and fed to a separate Scrolls, instead of separate Turbos.

I suppose this could have been for simplicity, or weight saving, or space saving reasons?

This is a diagram of the N54:

You can see what I mean where the Cylinders are split. Important to note though, the diagram is not 100% accurate. They show Cylinder 1-3 going to one Turbo & Cylinder 4-6 going to the other. I don't believe this is actually correct, it was merely for the diagram's sake.

http://www.autozine.org/technical_sc...rallel_BMW.jpg

Cheers,
Emile

Sasha,
If you still have any of those 1.5 kits available let me know.
Thank you.:tiphat:

Does this mate with the nismo exhaust yet or still only fast intentions?

Currently you can get the Fast Intentions or the OEM single mid-pipe flange for a Z. Only the OEM mid-pipe connection works on a G.

Thanks for quick response.



Sasha, would this be possible in the near future?
Im leaning here after the cluster f*** I'm currently in with G*M.

Just have it custom fab like most of us did.

Sasha will send you extra piping without the flanges welded so you can take it ot a shop to have it cut to size and flanges welded on.

I had mine done just like that and connected to the second to last section of my CNT exhaust. I feel like getting rid of my CNT exhaust and looking for something with no resonators.

I'm putting up a portable garage in anticipation for this kit. I can't wait!

:tup:

I am enjoying a long overdue vacation right now, but when I get back the production will resume.

Will you accept a deposite or just wait for them to be done and pay in full?

I'd like to get the kits close to complete before taking deposits.

I understand, if it were me I would feel like the deposits would be pressure

No one wants to pull a GTM. lol.

I thought it...You went there:tup: