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Bi Modal Air Intake

davey g-force

I'm a sceptic...
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I honestly had no idea what the benefit of a bi-modal intake was. Still seems like a bit of a wank to me, but the end result seems to be a more refined car (IE: Noise wise) without compromising performance.

According to the article, it actually INCREASES performance.
 

Not_An_Abba_Fan

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The bi-modal air intake has a valve that increases the amount of air sucked into the engine depending on throttle position and engine revs for extra power. When closed, torque (or pulling power) is enhanced at lower engine speeds.


Isn't that the job of the throttle body? A valve that increases the amount of air sucked into the engine? (Or pushed in to be absolutely correct).

What Kiddo said about the X pipe is spot on too. But the term X pipe only refers to the true X pipe, not a merge. People call a merge an X because it looks like one. A proper X pipe is shaped so that it actually directs the exhaust flow to the opposite bank, where as a merge is just an opening that acts like a balance tube. When done incorrectly, the merge is actually a restriction as it reduces the pipe size at the merge.

One exception is the Sureflo merge, it acts more like a pressure wave termination box than a merge anyway, whether by design or by accident, it actually works rather well.

Sorry to ramble on, but it's a bugbear for me when people refer to something that it is not. Especially with exhausts.
 

AirStrike

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Kiddo can confirm, but sounds like a similar setup as used on the Ford N/A I6, which if that is the case is a good thing. Allows good low down torque with, in effect, a shorter intake runner but allows the extra needed up top.
 

Kiddo

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The N/A I6's have a butterfly valve in the intake manifold, which does exactly as Strike said. Only downside is that its noisy as all hell. Kinda like blubblubblub below 3250rpm, then bwaaaaaaah above.

But it sounds like HSV have a system before the throttlebody, where's Ford's is after.
 

swingn_wasabi

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According to the article, it actually INCREASES performance.

In reality it may actually increase performance in areas, in the same way bi-modal type exhausts can increase down low performance if designed properly.

With all the technology that is going into cars these days, you'd expect they design & develop these things for a reason... I reckon the real indicator will be what the tuners do - IE: Will the intake get replaced with a standard type OTR & produce better numbers & real world performance?
 

PIR4TE

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Doesn't give much away...
y4ydumu2.jpg

The R8’s Electronic Driver Interface (EDI) is carried over from the preceding model, now displaying interactive mapping for the bi-modal exhaust, bi-modal air intake and stability control functions via an app on the MyLink system.
Still looking for more detail as it is very interesting.
 
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galahs

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In reality it may actually increase performance in areas, in the same way bi-modal type exhausts can increase down low performance if designed properly.

With all the technology that is going into cars these days, you'd expect they design & develop these things for a reason... I reckon the real indicator will be what the tuners do - IE: Will the intake get replaced with a standard type OTR & produce better numbers & real world performance?

This is what I am interested in knowing.
Is it a better system than an OTR.



Also according to MOTOR Magazine, the Exhaust Headers on the 340kw and GTS are hand made jobbies.
 

Not_An_Abba_Fan

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Probably more of an emissions control device to meet Euro 5 standards.

All exhaust tube style headers are hand made. No machine can put them in a jig and weld them up.
 

galahs

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Would it be fair to say the SV, GTS air box assembly probably offers better airflow than the W427 OTR
 

galahs

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Here's a picture of the MAF pipe on the SV models.





Looks much less restrictive than the base LS3 with its massive resonance chamber
trd_hsv_0009.jpg
 
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