F engine with kind of 2F block but still it is F

[DedVassaby]

Hi all!
Has anybody ever seen F engine in kind of "2F" block?
We've got the engine that marked as "F" on the number plate, but block is like from 2F, and oiling system and head with rockers are like from 2F, but cylinders dia is 90mm.
Oil filter already placed like on 2F, valve cap is from F155 - but this could be changed.
How is it possible??

 

[Pighead]

How is it possible??

It could be the 1.5 F, or the "Late F" engine, as we call it

 

[brian]

1974 model year only