Slash 2WD gearing

Hi Guy

i just recently bought a second hand slash 2wd a week ago
pretty much bog stock except for upgrading steering rack which i'm told gives twice as much steering angle as they normally get, i believe its out of a 4x4 or so i'm told.

my question is...i'm about to drop the 12t titan stock motor out for a brushless 10.5t system
what sort spur and pinion should i be looking at to much sure that i do cook anything.

cheers
sid

fast acceleration and short course 16 tooth pinon and 90 tooth spur.
high top speed long distanse hard surface 23 tooth pinon and 86 toot6h spur

if you want speed than a 23t 90t
if you are driving off road then 15t 90t
if you are driving on road than 19t 90t

19/86 is pretty good. At least for a Rustler VXL.