Dart Big M NON Siamesed Full Water Block MRK IV 31243344 BB Chevy

With deck heights of up to 9.800" and 10.200" and bore sizes of up to 4.310", the Big M Full Water Block gives you the versatility to build a wide variety of engine combinations. A true priority main system oils the main bearings before the lifters for added reliability. The Big M Full Water Block is fitted with 4 bolt main caps for bottom end strength. Features, Standard 9.800" and tall 10.200" deck heights available. Standard 4.250" or 4.310" bore sizes. Uses +.300" tall Gen VI style lifters. Modification for MRK IV style available. Scalloped outer water jacket walls improve coolant flow around the cylinder barrels to equalize temperatures.True priority main oiling lubricates the main bearings before the lifters. Our stepped main oil gallery (9/16" to 1/2" to 7/16") increases the flow of oil to the crank at high rpm, and our front oil crossover eliminates internal oil leaks around the distributor shaft. Oil filter pad is drilled and tapped for an external oil pump. Lifter valley head stud bosses prevent blown head gaskets. Mechanical fuel pump boss, clutch linkage mounts, and side and front motor mounts simplify installation in any chassis. 4 bolt main bearing caps in ductile iron have splayed outer bolts for extra strength. MRK IV blocks use the 2 piece rear seal design, while Gen V and Gen VI blocks use a 1 piece seal and a different timing cover pattern. Standard BBC cam and main bore. Coated cam bearings, freeze plugs and dowel pins are included.