XRAY - Model racing cars

I'm having a hard time with my 808 shocks on the XB8... more so with the rear. I tried silver springs with 1.3 pistons and 37.5... Car bottomed out super easily. So i went to grey-blue springs... A little better, but the car is rebounding really slowly compared to the front. So i went to a 5 piston with 32.5 weight, and it's even worse. The action going both downward, and rebounding feels very slow. I'm going to try 1.4 pistons, with which oil do you think? My track has some decent sized jumps that I don't want to bottom out too easily, but also want decent action... I built the shocks with 50% rebound, and foam in the bladder as well... Thanks for any help!!!!

i had mine set pretty soft on sunday and landed very nicely with 1.4 pistons,40 wt front,35 wt rear with 5mm rebound.

shocks on outside hole rear,mid on front on tower
outer on wishbone front,inner on rear
grey springs all round.

sometimes the car just bottoms out and you have to accept that,if you go too stiff you will start getting kick ups over ruts.