Fatboy joe....... what size carpet track you running on?
and as dave said a little less caster in the front. there is a guy i race with he has a R2 stock and runs it in the stock form out of the box but you have to use spacers to get the foams out from the hubs. or if you run carpet alot you can do like i did and invest in some excel hubs so the foams fit like they should .
as far as being stiff i think that would depend on your track . i like to have a little play on carpet my self.