I recently bought maisto tech 1:10 scale rc aventador      I am finding it a bit slow as I expected a high speed  for 6250 bucks 
it is installed with 7.2v  700mah battery       can I increase d speed ? plz help me out

change the esc and motor

what is an esc? its functioning?

what car do you have can you upload it's pics

Esc = electronic speed controller
It is used to provide power to the motor acc to the signal given to it by the receiver