Chevrolet Performance 12480175: 400 Cast Iron Bow Tie Sportsman Block (400 Mains) 1-piece rear main seal
400 Blocks
400 Bow Tie Sportsman Block CNC-machined cast iron competition block 4-bolt nodular mains (splayed caps on center 3 mains) 4.117" finished bore 350 Sized Mains Tall lifter bores Comes with Rear Seal Adapter 1-piece rear main seal