Wym, the Wallace calculator works with an entered value of ICA, so I think the answer to your question is no, it just uses that as the termination point for pressure release via the intake. I think you may be thinking of the Comp calculator, which IIRC works from .050" and makes some assumptions of how much later the valve effective closes. FWIW: For the Wallace and Pat Kelley calculators, I typically put in advertised unless it is for a solid, where I adjust from advertised to try to account for lash.
I personally agree very strongly with the tighter quench gap. And I like the 1.6 rockers but my hesitation of putting them with a Lunati Voodoo cam is that you are putting more force on the valvetrain with an already fast slope cam. Where I really hesitate is at the lifter/lobe interface. I bet peak pressures on the lifters and lobes will go up by >10% or more, with the 1.6 rockers. You get a mildly exponential increase since the force is related not just to the lift ratio, but is also increased by the increased valvetrain velocities. That same applies to the Voodoo and XE types cams: the valvetrain force goes up more than many folks may realize.
We put 1.6 rockers in my son's 340 but it was with a milder ramped Crane 268 cam.
