LiPo on a stock RC 18T?

[JOHNNYMAXXIMA]

Can a stock 18T use a LiPo. If so, how may cells? I actually have the Reedy Mini Max motor in there but stock controller.
The thing went 23mph stock, 27 mph with the Reedy motor, and I just put an 8 cell pack in there (vs. the stock 6 cell) and got 32mph. Yes the motor was a little warm, and may not last very long, but it sure was fun.
I plan on going brushless with it in the future.
Thanks.