Small size, big performance extruding machine !

Warning:
This extruder after many month of good services has been superseded by a newer design, a bit lighter more compact using Nema 14 motor and gears used in RC cars. The concept is the same though. Can be seen here: https://www.thingiverse.com/thing:2594693
I keep it here to show what can be done and inspire knowledgeable people to design their own.

Here is a video of a print (20mm test cube Feed pushed to 300%,180mm/s). REAL SPEED !
https://vimeo.com/251363819

I do not provide parts list and detailed instructions because I used parts scavenged from old printers and not readily available.
One can adapt to what they can find.
Now once I find a reliable source of ad hoc parts, I may complete the description.
Overall size could be reduced provided smaller, different gears are used but what is important is reduced weight, reduced GC to X:Z plane, reduced filament travel, reduced distance from the X axis, reduced distance to the hot end tip.

The Titan extruders are t