brodix alum bbc block with blown head gaskets-liners dropped

[badbug3]

have a 572 bbc quad whipple fuel injected 1280 hp engine in eliminator boat and for the last 3 years have been running fine with the merlin 2 block. Now just installed a brand new brodix aluminum block to save weight and it only made 10-15 passes before it blew the cometic head gasket between cylinder 5 and 7. After tear down we noticed the liners have dropped a few thousands and probably caused this problem. Block was prepared from well known engine shop in new orleans. WHAT CAUSED THE LINERS TO DROP? SHOULDNT THE LINERS HAVE BEEN SEATED WHEN THE BLOCK WAS HONED WITH THE DECK PLATES AND THEN DECKED LAST?

[billhendren]

All new blocks need to have the sleeves seated before decking. the blocks are heated to install the sleeves and the aluminum shrinks approximately twice as far as the iron sleeve.Bill