hmm just thought of something. what about two 5s1p packs, one on each side.. the problem I see with that, is that the drive belt isn't in the center, and that would push the weight way to the outside.. almost to the full width of the car..
then again, they are alot lighter.. but then i could mount the rest of the elctronics realy low on the chassis in the center.

the front has a one way in it..
i'm not familiar w/ nitro, oneways, and or 1/8 onroad drivetrains.. the rear doesn't seem like a differential. if I hold the center drive train, and spin one tire, it's very tight, but opposite wheel doesn't move..
it all seems very weird to me, having so many drivetrain changes i'm not used to at once. how could I lock the 2speed to the smaller spur gear? it spins and does nothing.. so centrifical*?
the drivetrain also seems very tight. not sure if something's binding or not.

I bought the car as a display model, with the car, and nothing else. i don't even have an instruction manual! =\. the discount was worth it imho. I'll probably rebuild the car completely before I run it to check the drivetrain.