BBC IR/BLK SPORTS 10.200-4.250 NO K

The Dart Big M Sportsman Cast Iron Block (PN: 31223354) is engineered to be a strong, reliable, and easy-to-build big block engine. It features a 10.200" deck height and a standard 4.250" bore, with siamesed extra-thick cylinder walls to resist cracking and improve ring seal (minimum 0.300" thick with a 4.625" bore). This block uses +.300" tall Gen VI style lifters. The 4-bolt ductile iron main bearing caps have splayed outer bolts for added strength. It incorporates a true priority main oil system that lubricates the main bearings before the lifters, with a stepped main oil gallery (9/16" to 1/2" to 7/16") to increase oil flow to the crank at high RPM. A front oil crossover eliminates internal oil leaks around the distributor shaft. Lifter valley head stud bosses prevent blown head gaskets, and dual oil pan bolt patterns accommodate standard and notched oil pans.