only 13T and it goes so nice? I have also a 13,5T motor! it means,it won't go so bad

what pinion do you have on that 13T motor? I've bought yesterday a 27T pinion for the torquey motor.
I see that you have painted your car to green

I also bought yesterday a white paint. soon my car will have a new look
And one more thing. I just ordered 2 lipos, 2s 4000mAh from hobbyking for 19$ a piece,with a set of 3,5mm and another of 4mm golden bullet connectors.