Hey guys,

Anyone here have any data on rubbing B series ITB's with IACV for idle control? Skunk2 has the IACV relocation kit which in theory would allow one to use the IACV still to retain ease of tuning and drivability.

I tried searching but couldn't pull up any info. From my understanding, most just peg the throttles slightly open with the adjustment screw and call it a day.

 

How exactly would you plumb an IACV properly on a set of ITB's since there is no intake plenum ? I suppose one could add a port in each of the individual runners, sub-divide the metered side of the IACV into four outputs and connect to each runner port... and in theory, it should work.

 

Right, which is the theory here as well. When running ITB's, a vacuum manifold is needed anyway so the ITB's would need a port from each runner to the vacuum manifold, which my set has. You could simply plumb the IACV to the vacuum manifold and it *should* have the same effect.

My worry would be if the IACV would effect overall vacuum levels enough to cause issues with vacuum related components like the MAP. But, when looking at a stock manifold, the IACV opens a bridge between the manifold and open air just outside the throttle blade which also has an effect on vacuum levels. And the MAP feeds off of the same area that the IACV removes vacuum- literally an inch or two away. So.. it should work?

 

I figured I would put in my $0.02 worth here. If you require constant vacuum for other systems, brakes, emissions etc... you will want to have a separate vacuum box/manifold with an inline check valve installed to maintain vacuum when under low vacuum conditions. Your IAC valve and MAP sensor should be connected to a separate vacuum box/manifold that is directly connected to each runner.