well mr chryslerman6772 tell me how in the hell do fenderwell headers devalue a 70 dart? how many 70 darts came with a 440 in them stock, I have had and raced about 5 big block darts, my current is a 72 swinger 440, in 4 off them I had fenderwells, and one was a hemi, but I have never had problem them, they are are not for light weights who have an inch and 7/8 pipes, but for those who want the most power out of their engine, I think people that are afraid to use them is because it is beyond their technical expertise.