The internal ratio of the ZX5 is 2.5:1
FDR is dependent on your spur and pinon choice and tire size.
I would recommend titanium tie rods as well.
TLR/Losi Team Driver
TLR/Losi | Tekin | Venom | DE Racing | Spektrum | Exotek | JBRL | Kolor Koncepts | OC/RC |Sticky Kicks | Imagine It Graphics | Casper-RC.com
TLR 22 3.0, TLR 22SCT 2.0, TLR 22-4 2.0, TLR Ten-SCTE 3.0, Spektrum DX6R
WWW.CASPER-RC.COM TLR and Tekin setups