[Gilliaml]

I currently have a BBC Block casting # 361959. Is this block considered one of the preferred casting numbers to build and what would be the maximum over-sized bore for this block?

[1971BB427]

Your casting number is a '73-'85 BBC 454 car/truck motor. Pretty common and standard engine. Maximum over bore is not what I'd consider, as it leaves you nothing in the future. Some 454's have been bored .125", but each has to be looked at for core shift, or other indications of a possibble issue when going that far.
Most people would consider .060" as a safe maximum that doesn't require any special work to determine cyl. wall thickness. I personally like to stick with .040" max, as it leaves me another safe step if I ever need it.

[Gilliaml]

Thanks for your follow up. I have heard some casting number blocks are are better than others so I was curious if this was one of the better blocks. Thanks Again!