Variable intake valve timing. Variable geometry composite intake manifold
06-20-2001, 09:51 AM
#1
New Member
Thread Starter
Join Date: Mar 2000
Posts: 305
Likes: 0
Received 0 Likes
on
0 Posts
Variable intake valve timing. Variable geometry composite intake manifold
Can anyone explain these S4 "features" in more detail?
VIVT - At what RPM does it kick in?
VGCIM - What is the mechanism to "vary" the geometry, and what is the criteria? What does the "composite" refer too?
Ming
VIVT - At what RPM does it kick in?
VGCIM - What is the mechanism to "vary" the geometry, and what is the criteria? What does the "composite" refer too?
Ming
06-20-2001, 09:54 AM
#2
AudiWorld Super User
Join Date: Nov 2000
Posts: 4,731
Likes: 0
Received 0 Likes
on
0 Posts
I'm not an expert but....
I know the VVT is constant, not like VTEC. And I believe the intake manifold is made of some kind of composite. Correct me if I'm wrong...Not positive.
06-20-2001, 09:57 AM
#3
AudiWorld Super User
Join Date: Mar 2000
Posts: 15,685
Likes: 0
Received 0 Likes
on
0 Posts
VVT...look up Vanos (BMW version) or Cam phasing (nissian 1990's version) ... VGC is NOT on the S4
fargin PR guys!
the composite would refer to a material other than metal (plastic, Carbon fiber, fiberglass..etc)
the composite would refer to a material other than metal (plastic, Carbon fiber, fiberglass..etc)
Trending Topics
06-20-2001, 11:59 AM
#8
New Member
Join Date: Jan 2001
Posts: 154
Likes: 0
Received 0 Likes
on
0 Posts
intake answers
A variable geometry intake is set up typically like the following.
The main intake plenum is split the long way into two narrower plenums. There are cross over butterfly valves between the plenums (one or more) by opening or closing these valves, the resonant frequency of the manifold is changed, so you can optimize breathing over a wide range of rpm.
If you want to learn more about really high tech intake / valve stuff, try to find the book "21st Century Performance" its an australian book, but you can order it online and its worth every penny, it explains everything from tires to turbos to intakes and cams.
-m
The main intake plenum is split the long way into two narrower plenums. There are cross over butterfly valves between the plenums (one or more) by opening or closing these valves, the resonant frequency of the manifold is changed, so you can optimize breathing over a wide range of rpm.
If you want to learn more about really high tech intake / valve stuff, try to find the book "21st Century Performance" its an australian book, but you can order it online and its worth every penny, it explains everything from tires to turbos to intakes and cams.
-m
06-20-2001, 01:30 PM
#10
New Member
Join Date: Jan 2001
Posts: 154
Likes: 0
Received 0 Likes
on
0 Posts
Re: Based on your description, I don't think the S4 has VGI?
the S4 does have variable geometry intake (at least according to audi) so I think it takes the form of just a little valve in the intake plenum (behind the throttle body, probably on the back side of the motor, I'll poke around tonight and try to find it
-m
-m