Intake Header

[vwtype53 at yahoo.com (Ben Harder)]

Hey guys... this is indeed a great topic.  So great indeed that I spent my
entire senior year as a ME designing, fabricating and testing a new
"marketable" intake manifold for the 16v... here's just a hint of what I
created...

http://www.geocities.com/vwtype53/dynochart.jpg

Not bad, eh?
Just a simple intake manifold swap (upper half only), and all that extra power
up top.  Without any losses at lower rpm, it's a shame VW didn't do a little
more homework like I did...  :/
(even used the stock throttle body...)

I learned a lot about Helmholtz tuning, positive and negetive pulses, and the
effects of chaging volume, length, and parameters of the intake plenum and
runners.

Ben



--- GTG <NavySEAL2B@insightbb.com> wrote:

> You mean like tuning the length of the intake runners?  Because yes, that 
> does help, similar to scavenging as you've said.  Do you have some sort of 
> design in mind?  If you're interested in making a really good intake system 
> without doing any ridiculous physics, look at existing designs.  First 
> things that come to mind for me (I'm a Bimmer guy) are the Euro S50 engine, 
> S14 (esp the Carbon manis for their race cars), and Dinan Z8 intake systems.
> 
> Some reading material:
>
http://www.google.com/search?hl=en&lr=&c2coff=1&q=helmholtz+equation+intake+manifold&btnG=Search
> Vortex also has several threads having to do with the helmholtz principle 
> and intake systems.
> I skimmed through the first few links there and they look pretty useful. 
> I'm working with wave physics right now in school, and most of the math is 
> barely beyond the level of a good college level physics 1 course.  Waves and 
> fluid dynamics are responsible for the "scavenging" effect you're looking 
> for.  The scavenging comes from waves, though, which only produce the right 
> effect at or very near certain frequencies, which is why it will be most 
> effective in a narrow RPM band.  Some more modern engines have variable 
> length intake runners (along with the variable valves and such) to optimize 
> for several different RPMs.
> I've also heard that polishing the inside of intake runners is not a good 
> idea because a rough surface actually creates better flow.  I suppose that 
> doesn't include the area right up at the valves since polishing is so 
> popular there, but that might be something to look into as well.
> 
> -Grant-
> Annapolis, MD/Louisville, KY
> 1980 in storage :(
> 
> 
> 
> ----- Original Message ----- 
> From: "Kervin Ridgley" <carsandkites@gmail.com>
> To: <scirocco-l@scirocco.org>
> Sent: Tuesday, November 30, 2004 12:04 PM
> Subject: Intake Header
> 
> 
> >I was thinking about ways to get the the intake side to flow better.
> > Would something like a intake header help.  By spacing out the intake
> > sucks (you know, the opposite of exhaust pulses), would it "scavenge"
> > more air in?  Just a crazy idea I was having.
> >
> > Kervin
> >



		
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