XRAY - Model racing cars

I've a question: how do you guys decide what setup you put on the car (808e) or what is the best setup a astrotrack? I thought like 7-10-5 but I don't know if it's good.

for astro style tracks.. the thicker diffs are good.. i think your diff setup will be fine..

American style, big tracks we go a little lower in diff oils.

Thanks!! I've the setup in my car now and now I have a question about the shock setup. 1 friend drives 600-450. I don't know witch setup is good for astro. After a jump, the back of the car is bouncing. I drive on this moment 600-650 but I want some better. Does anyone know a better shocksetup for astro?