I'm probably not the best person to advise you, thought paul would of with his setup.
The carpet is pretty high grip with pins, the tarp that we will have down though is pretty slippy, especially in the first round untill the dust has come off the racing line a bit!
Richard lowes off
http://www.rc10b4.com/forum/showthread.php?t=2611 is probably a good starter.
EDIT: tried to attach mine as PDF but nothing happened so here it is... I run lipos though with no extra weight so you might find the shocks to soft..
FRONT
30deg caster
Trailing arm
CAMBER LINK - 1A / 1washer
ARM - Inside
Tower - Middle
SHOCKS - Silver/35/no2
Rear
Short wheelbase
CAMBER LINK - 1B / (i have the newer rear bulkhead that has the bump thats same height as 2
washers)
ARM - Inside
TOWER - Inside
SHOCKS - Silver/30/no1
Antisquat - 2degrees
Camber - -2
Ride height - arms and shafts level
Its pretty much what i run outside only i stick green springs on back for outdoors!!
I find with the lipo and the 19t i have more than enough go for the fomby track.
I'll be running 4wd at the GP