are the 03 and 04 cobras 4 valve like the new 5.0s? found a nice 03 cobra, has 65,000 miles, lotts of mods, claims 479 hp, on dyno, wants 18 for it, its a convertible , really looking for the coupe, drove a few 03 cobras then test drove the new 5.0 , the 5.0 seemed to have more low end power...