Sounds a whole lot like the 65 Dart I bought in 67 with a two seventy three ( my three key quit working) 4 speed. It had 11 to 1 pistons with a Racer Brown ST-21 Cam . It had 2 AFB 500 CFM carbs( that I changed to a single one) It had 4.86 gears . I made a lot of SS Chevy's cry with that car