first off, afm, i with a lot of others, will think tires are most important, if you dont have the right tires you might as well go home. second, 1 way or diff in the front, if you run a diff fill it with 30k and you will be fine. all the tracks i have been to have been this way.
my setup as of now. tires may change but this setup works awesome on most tracks.
toe 1 out
roll bar level
shocks stock: ver 0201
front tires 42 shore power tyres 26mm
rear tires: 40 shore power tyres 30mm
works awesome for me at most tracks, if there is more traction, i go to a 45, 42 if there is less i go to a 40, 37.
if it is a big track i run a 1 way and a negitive diff.