IM= Intake Manifold. On most turbo's you have a vacuum port at the opening of the outlet on the compressor (opposite exhaust) side of the turbo. If one isn't available there, you can tap the same line as you BOV. The most efficient way to add vac lines is to by a brake booster tap. That's where the most volume is for any line in the system, it's the big half inch thick line connected to the brake booster. (Big round thing that holds the brake fluid resivoir on the driver side). This is best done using the Golden Eagle vacuum block.



You can get them on the e-bay for around 40 bones.

I personally have my BOV tapped off the manifold and my wastegate and EBC (electronic boost controller) solenoid tapped off the turbo and find no need for one of these things. But it's an awesome upgrade.