IAB's

[reckedracing]

this has a mechanical function in the intake right?

i'm just trying to figure out exactly what it does, where it is, and why its important...

if there's a write-up just point me to it and e-slap the shit out of me...

 

[posol]

iuts a butterfly valve.

it opens/closes to effectively change the length of the itnake runners.

shoter runners are good for high end hp
longer runners are good for low end torque.

throw an electronic device on there, and you get the best of both worlds....



edit- i might have the longer/shorter words messed up... i'm double checking myself...
edit 2- verified correct

As a general rule, larger plenum, short-runner manifold designs are usually more effective for making high-rpm power

 

[reckedracing]

hmmm, perhaps i can find a pic somewhere...

would this IAB be located between the large chamber and the actual runners?
there appears to be a plate in between the "chamber" that the throttle body bolts to and the runners...

and how does the butterfly alter the length...

 

[posol]

basically you have a long path, and a short path...
when the valve is open, it takes the long path
when its closed, it takes the short path.

the short path kinda "cuts the corner"

 

[reckedracing]

http://www.we-todd-did-racing.com/wetoddim...kZmQzMXk1NDE%3D

pic

so what does that sensor for the IAB do?

and the thing right above it in the pic, with the vac line and the little arm with a spring...

says the sensor is for IAB, but what does it measure? air flow?
and i'm guessing the mechaincal part of the IAB is the thing right above the sensor?

 

[dohcvtec_accord]

The sensor in that pic is the IAT. The sensor for the IAB's is connected to the vacuum cannister. It's not completely neccesary to have the vacuum cannister hooked up (I had a vacuum line running directly to the manifold), but I believe you still need the sensor connected to the vacuum cannister.

The thing with the vac line and the spring is the actuator for the IAB.