Dart engineered the Big M to be the strongest, most reliable, and easiest to build big-block on the market. 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.
Dart machines Big M blocks in-house on precision CNC equipment to ensure quality and to eliminate the need for expensive “blueprinting.”
Specs | Material | Deck Height | Bore Diameter | Main Bearings | Camshaft | Main Caps | Oil Pan |
Big M | Cast Iron | 9.800" 10.200" | 4.200" 4.500" | BBC | Standard BBC | Nodular Iron or Steel 4 - Bolt | Standard BBC with Dual Bolt Pattern |
