not to prolong this thread but the 428 CJ was actually "developed" at Tasca Ford in RI. bob tasca, the owner, was big into racing and the 390 mustang wasn't cutting it. so he had his mechanics came up with a better engine combo and they used a mix of 428 police interceptor and 427 parts. after they dialed it in and were sucessful drag racing with their combo bob called ford and had them see what he had done. the rest is history.