Quote Originally Posted by stylingZ
I am looking at a BBC 511ci which supposedly has been made out of a 454 which has 4 bolt mains. I've never heard of this before so I'm hoping Pat or Erik will help me out? Just how far out would you have to bore a 454 to get 511ci and would the walls be paper thin? I don't want to commit myself until I know more of what I am looking at. Originally I am considering building a 496 stroker, but the price of this 511ci is very good.
A 511 is a 4.375 bore X a 4.25 stroke.
This can be done using a stock block which is bored .125 over.
At this over-bore the walls can be paper thin.
I.M.O.,this is the very MAX. you can ever go on a stock 454 block.
It won't leave any room for clean-up.
I would not buy un-less the block has been sonic tested and you know who did the testing.
Even then it would bother me.