Butterfly valves in PD intake ports

[foobert]

Looking through Burpod's turbo install pics http://picasaweb.google.com/burpod/TurboInstall

and I was struck by this oddity:
http://lh4.ggpht.com/burpod/SIf4ebNHZEI/AAAAAAAABLg/vWi2UD2lRqs/manifold_9.jpg?imgmax=720

http://lh4.ggpht.com/burpod/SIf4ebNHZEI/AAAAAAAABLg/vWi2UD2lRqs/manifold_9.jpg?imgmax=720
Why-o-why would they split the intake port and close off ~1/4 of it?

Ugh. All I see here is inefficiency...

 

[nicklockard]

There's already a big thread on it. The consensus was that it is there to induce swirl across a broader rpm range, thus increasing torque and power for a given emission.

 

[foobert]

That was fast. Thanks. I'll have to do even more searching and find it.

One of my pet peeves about the forums is the tedium required when searching for something. Unless the title of the thread happens to match perfectly, one has to wade through countless useless threads to determine if, in fact, they are useless.

 

[Nico3d3]

One of my pet peeves about the forums is the tedium required when searching for something

Totally agree with you, unfortunately a lot of forums search functions has the same problem.

 

[burpod]

i don't think there was any consensus on what exactly they do - lots of theories but no "hard facts". why wouldn't a pd150 have this magical technology if it was so good? my theory is it has to do with meeting the US emissions and works in conjuction with the ASV and EGR...

so... anyone got any *real* info on what they do, and not just theories?

link to original thread:
http://forums.tdiclub.com/showthread.php?t=130787

edit.. wow! someone actually looked at my pics!!

 

[foobert]

wow! someone actually looked at my pics!!

Heck yeah -- great pics! Let's me know what I'm going to be in for when my k39 goes tango uniform and a VNT 17 (or, maybe more!) goes in.

Thanks for the link to the other thread. Interesting stuff.

 

[nicklockard]

Well I think you might benefit by reading the "how to search" thread because you don't search by threads, you must click on the 'search by posts' and boolean. Then zero down the time frame to one year ago and older for this particular search.

Grasshopper, you must learn the ways of search. Use the force

Try not! Do.