Engine from is already enough powerful. Some people are thinking that Hellcat has even more power as is needed on our roads. But engine is really good. So Chrysler already inserted it in almost all his big RWD and AWD cars and SUV. But some people from Hennessey are sure that Grand Cherokee Trackhawk with engine from Hellcat is not enough powerful and fast. And spends too little fuel. So they fixed all these mistakes!