[Extruder] Configuring rotation parameters

Hi again people,
I was searching through the wiki time ago and spotted (randomly) in a page that was describing how to calculate, by measuring the gear's parts, what to set for the extruding speed/mm whatever...

Now I can't find it anymore, or remember how I got there, someone knows how to get to that information?

I'm using a 1.75mm + wade so I'll have to deviate from the standard configuration, of course.

There, tried printing these two pieces (from left to right: minimug and knob)
[picasaweb.google.com]

I've tried to cut in half te width and heights of the extruder, but it seems it's not enough.
I suspect the default extrusions considers a 3mm filament, so when rotating it expects to put through more material than it's actually going down there.
I'm not yet sure which other paramter to set, and yet didn't find that wiki page...