Thanks for the additional info.
I'm not keen on the possibility of a touchy clutch, and I understand multidisc clutches can be noisy with all of those parts rattling around.
Also, rotational inertia is a good thing as far as drivability, as it lowers the driveline torsional resonance frequency*.
But back to the original question, do you know the diameter of the M3W flywheel and/or clutch disc?
I figure if I use at least as big a single-plate clutch I should be fine, as the M8 has about 10% less displacement than the X-Wedge, and for the most part I'm easy on clutches.
* Interesting and educational articles here:
http://www.epi-eng.com/propeller_reduction_technology/torsional_vibration_issues.htm (this is about propeller reduction gearbox systems, but fully applicable to automotive power transmission)
http://www.epi-eng.com/mechanical_engineering_basics/transmissibility.htm
