Chev BB Big M Cast Iron Bare Block

Dart's popular line of Big M2 blocks just got bigger and more competition focused, with five new part numbers. These new Big M2 block part numbers will feature 55mm roller cam tunnels, larger.904in lifter bores, doweled main caps and raised lifter oil galleries. These features represent the most demanded block upgrades requested by racers, now combined into convenient packages for easy ordering and to better meet our customer's and builder's needs Standard 9.800" and tall 10.200" deck heights. Standard 4.250", 4.500", 4.560" or 4.600" bore sizes with siamesed extra thick cylinder walls to resist cracking and improve ring seal (minimum.300" thick with 4.625" bore)