The heads and intake on the F code were different also. And, obviously the carb on the F code was a completely different animal.
We went through this on the cams a year or two back. The consensus was that most E/F codes came with the 256 degree std. 57 cam. The "Blower Cam" was also used, Don't really know if it was a factory or dealer installation. Maybe Hoosier can shed light on that. There are indications that there might have been a third, more radical cam used on some (early?) cars. Dennis K had some specs on that one.
However, if the car was modified, as you said, the cam is most likely an aftermarket, ( ISKY or comparable,) cam anyway.
Frank/Rebop
Bristol, In ( by Elkhart) 
