Electric Motor Pinion Change

[fracture14]

Hello all,

I have recently purchased a 2nd hand Tamiya TL-01, I've fitted an Ansmann 14x2T brushed motor and a Etronix speed controller. I am wanting to play around with performance and gearing.

I am sorry if this problem has already been asked but can you just add a bigger pinion on your motor I think the biggest I can fit on the car is a 25T, but if I do this do I have to change to spur gears?

And am I right in thinking that the bigger the pinion the higher the topspeed and smaller the quicker the acceleration.

Appreciate your time!