With the mapping I have been filling in the gaps from rolling road. Cruising fuel tables and suchs. Little modification to the fuel maps on WOT situations too, but everything I've done have been done in a way the mapper told me.
Ignition maps I haven't changed because they are pretty good already. Only idle advances have been changed after rolling road.

My tires are Kumho KU37 ECSTA if I remember the whole name correctly.
They seem to have pretty smooth grip loss curve which is probably reason for the almost like LSD action. Of course on the more drastic situations it doesn't help and only one wheel spins.

I've also heard that most of the Cossie viscous diffs aren't that good, but at least the one I bought the seller told me that it had worked very well on a 500 bhp car. Hopefully it's true.

About the cams, maybe with short duration karlthomas is meaning similar cams than I have too. They are short duration cams when comparing to the other performance cams out there, but still more duration than stock cams have. Decent duration and lots of lift makes for a good torquish turbo engine.
You can run high duration on turbo engine (you need that for extreme power), but it just means it will be even more laggier on the low rpms.