Billet Steel Main Caps
Bore Size: 4.500 Deck Height: 9.800
Dart engineered the Big M to be the strongest, most reliable, and easiest to build big-block on the market. With available deck heights of 9.800" and 10.200" and bore sizes of 4.250", 4.500" and 4.600", the Big M gives you the versatility to build a wide variety of engine combinations. We redesigned the lubrication system to create a true priority main system that oils all of the main bearings before the lifters for extra reliability. 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. The result: more oil at the bearings and pushrods where it’s needed, and less power-robbing crankcase windage. We added two slotted head stud bosses on both sides of the lifter valley so you can use studs instead of hard-to-install bolts to take the place of the “missing” head bolts.
Your block can arrive ready to assemble with freeze plugs installed, camshaft bearings installed and the cylinder block machined to your specifications. Please contact us regarding pricing for this additional feature.