Heads, what are these ?

Ok what I know is they have headers that are fitting on to 340 heads so this was one reason they ere thought to be 340.

@Locomotion
As for the pushrod work, you are dead on as they are not straight like the stock heads, there was extensive work done on the heads, I would assume by Mr Hamburger himself, as they are similar to the T/A head set up.

Thanks again guys.