3969854 engine block

[Kristoffer]

Hello

I friend of mine have a cbb Engine. It was assembled and it sopposed to be an 454. We took it apart, and found a 454 crank, 3/8 rods ect. But the casting is a 3969854, late 69 block, 4-bolt. I have looked all over the internet and in books, and the casting numbers tell it is a 396 (402) block, becasue it doesnt have the huge reliefs into the bottom of te cylinders as the 454 block has.
This block was also 0,30 bored, 4,280", how is this possible? Ive Heard of 396 bored out to 454 (4,250), but 454 + 0,30?

And this casting #854 with 4-bolt main, from what I can understand it is a L78 block? correct? The block it decked and there is no vin where the oilfilter is. It there any other way to tell what sort of block it is?

Thank You
Kristoffer