Hello, i finally got my car ready but the starter won't turn it over. I have a 9.5 with a hyper .21, the box i have has a 550 type motor that uses two 7.2 volt ni-cads, i charged them but it does not have much power, this is my first box and i'm confused. I see some boxes have a large motor which uses a 12 volt deal, will these boxes do the trick, any help would be great, Thanks.