Quote Originally Posted by Oldf100fordman
I don't know what they are for but definitely not for a 390 or any other FE motor. The tubes and flanges are spaced all wrong for a FE and the bolt pattern is wrong too.
Actually it's possible that these could be headers for an FE in a Mustang, Fairlane or Torino. The factory FE heads used on these cars had a bolt pattern like this. This was because of the close confines of the engine compartments in these cars, due to the shock towers in Ford's uni-body cars of the era. Many FE headers I've seen, regardless of application, have both bolt patterns so they'll work with either port design.