THat challenger had to be a 5.7 car not a 6.1 and there should be some sorta rule about all v8s haveing a sure grip grip .I will have to see how well the 6.1 lanches or I will be changeing gears right away.I already plan some sort of upgrades I want at least 500 plus horse .I have drove several 500 shelbys are there a pretty fun car and easy to turn 600 hp .My shelby 350 is superchargerd and had a whole list of other things done and trust me 425 hp isnt enough .I dont abuse my cars but I do plan on enjoying them to the fullest .