what are these headers?

[Racingduster]

I was cleaning the barn and found these headers. Just wondering what you guys think they fit. Small Block or Big Block? Think they are A body?

Thanks

 

[abodyjoe]

big block something

 

[Racingduster]

big block something

Thats what I thought also. Just wasnt sure

 

[cudamark]

Yup, big block but judging by the drop, they look truck or van to me......What do they measure from head flange straight down, even with the lowest pipe?