GM Performance Chev LSX376 V8 Cast Iron 4.065" Bore Production Block # 19417352Engine Block, LSX Bowtie, Bare, Cast Iron, 6 bolt Main Bolt Style, 9. 260 in. Standard Deck, Chevrolet, Each Main Journal Type: Chevy LS Engine Block Material: Cast iron Engine Block Style: OEM Engine Block Deck Height: Standard deck Deck Height (in.): 9. 260 in. Cylinder Bore as Shipped: 4. 065 in. Engine Block Weight (lbs.): 225 lbs. Main Bolt Style: 6 bolt Main Caps Included: Yes Main Cap Material: Billet steel Main Cap Fasteners Included: Yes Main