Rino ... there is no point trying to push the FJ to a gazillion mph ... the fuse is too draggy. If you want the FJ to go fast you need a very hot set up, to get that you need more battery and motor, that increases the AUW. I tried a 6S set up and was not impressed at all, even then I used 2,200 mAh packs of which I really bloated. On 6S she handles really lousy, relatively that is. Many have spoken about this and many agree a 4S set up is best, enough speed without sacrificing much of the handling characteristic. Best for me was a 4S 2,500 pack and a 16/15/3 with a 4.75 x 4.75.