Well, it is based on Fiat 850 technique. You can see details if you google Fiat 133. Also google "jokkis" on Youtube and you can see videos about Finnish car races where most of these have been destroyed. They replace the engines with something up to 200 hp of power at the back of the car. No wonder that some of those will leave the start line with front wheels in the air.
Mine is original and is in street condition.