Nothing out of the ordinary here, instead it's just your average factory stock Gen IV LS2 aluminum block. The original 4.00-inch bore was machined at A.R.E. Performance to 4.010-inch. By combining the 4-inch Lunati crankshaft to the new bore put us at 404 ci. For bearings, we went with a set of Clevite H-series pieces that are great for most performance applications, especially those you plan to hit the upper rpm range with.