Guys!
Come on. The cap used for the flash is a highly dangerous thing, capible of holding charges of several thousands volts. so there have to be uses for it on the micro RC cars.
Swap the camera capacitor for the one under your PCB. More capacatance is good, and it's unlikely that the stock battery will be able to charge it enough to hurt your board. (try on cheap clone you don't like first though) If it works, you should have better acceleration. If not, you should put the fire out quickly.