Dart Big M Race Series Aluminum Block 31264645 BB Chevy

Standard 4.840" or 4.900" spread bore spacing provide large bore capacity. The camshaft is raised .400" above the stock location to increase clearance for the connecting rods and crankshaft counter weights, and the main oil gallery is located alongside the camshaft tunnel to eliminate interference with the crank assembly. Advanced engineering makes Dart aluminum big blocks the choice for serious competition. Features, Premium alloy: Dart aluminum blocks are cast from virgin 355-T61 aerospace alloy for superior strength and integrity. Ductile iron sleeves with extra thick cylinder walls promote excellent ring seal. Reinforcing ribs strengthen the lifter valley bellhousing flange. Inboard valley head stud bosses improve gasket sealing. Priority main oiling system delivers oil directly to the crankshaft bearings to enhance reliability at high engine speeds. Standard BBC cam journals, up to 60mm with raised cam options available. Standard .842" BBC lifter bores, other options also available. With or without distributor provision. Steel 4 bolt main caps with splayed outer bolts for extra strength. Light-weight aluminum caps also available. Mechanical fuel pump boss, clutch linkage mounts, and side and front motor mounts simplify installation in any chassis. Dual oil pan bolt patterns fit standard and notched oil pans. average weight 140lbs.