My local astro track is even more grippy than normal astroturf in the dry.
On my HPI Vorza I run:
Schumacher yellow mini pins
http://www.racing-cars.com/pp/Produc...rts/U6723.html
Fastrax green inserts (hard)
http://www.modelsport.co.uk/fastrax-...roducts/366660
HotBodies oversize 1/8th buggy wheels
http://www.hpiracing.com/en/part/67527
The combination of oversize wheel and hard insert/tyre compound gets rid of some side grip and allows you to push a buggy harder without grip rolling. This setup has consistently given me my best lap time on dry astro BUT self-discipline is essential, the car will still have a lot of side grip so you must do all your braking and jumping in a straight line.
Also i've adapted a rear sway bar to fit on the front which makes a difference (0.5mm thicker) and I run hard springs with the shocks on the outer hole on the tower.
At this time of year you might also want to get some of these for when it's wet:
http://www.racing-cars.com/pp/Produc...rts/U6751.html
And some of these for when it's really wet (i.e puddles on track):
http://www.racing-cars.com/pp/Produc...rts/U6757.html
Hope this helps!