you could try less pack in the rear to speed up the rebound(bigger piston holes).If you're happy with it in most situations though you could just leave it and deal with it from the transmitter.
edit;hey,cross post,spooky,i was thinking he meant the rear was staying packed down on the face of the jump.
so i dont need to use stiffer sping to prevent the rear to go down while jumping bec ithought using a stiffer spring in th rear will make the truck the tendency to nose dive
Brushless Jammin Truggy on NEU 1515 2.5 D on Monster mamba max with maxamps 5000mah 6s Lipo
Gorillamaxx Revo CF version on Mamba maxx ESC with NEU 1515 1Y on Maxamps 4s 8000mah Lipo