I'd just change the servo to a faster one to be honest.
If indoors I'd add an under LiPo and Servo weight from Trishbits or Rudebits. Ask them for advice and they will give
We've been running an B4 RTR for 6 months and its been faultless.
Change the servo to maybe a Savox 1251 and you'll be laughing. I would worry about the radio set up (unless you want sticks.
The speedo program guide is here:
http://teamassociated.com/pdf/cars_a...esc_manual.pdf
It comes set up but you might want to fine tune the brakes etc etc. Word of note, do not move the wheel/sticks/trigger when turning the car ON or it will reset settings on the speed controller.
As for LiPo's well any cells over 4800 and 30c will last you two races.
PM me if you need more help.
Neil