Iron Blocks W/Ductile Iron Main Caps
- Ductile iron 4-bolt mains caps for ultimate bottom-end strength
- Siamesed extra thick cylinder walls to resist cracking and improve ring seal (minimum .300 in. thick with 4.625 in. bore)
- Uses +.300 in. tall GM Gen VI style lifters
- Crankshaft tunnel has clearance for a 4.500 in. stroke with steel rods without grinding
- Main bearing caps have splayed outer bolts for extra strength
- True priority main oil system lubricates the main bearings before the lifters
- Stepped main oil gallery (9/16 in. to 1/2 in. to 7/16 in.) increases the flow of oil to the crankshaft at high RPM, and front oil crossover eliminates internal oil leaks around the distributor shaft
- Lifter valley head stud bosses prevent blown head gaskets
- Dual oil pan bolt patterns fit standard and notched oil pans
- 220 BHN cast iron block material
- .842 in. lifter bores
- Press-fit freeze plugs
- 2-Piece rear main seal
- Block parts kit sold separately - 301-32000002
The Strongest and Most Reliable Big Block Available!
Dart has reinvented the "Rat Motor" with their cast-iron Big M big blocks. Working with top builders and Dart's own championship-winning Pro Stock engine department, they have designed a no-compromise, user-friendly block that solves the problems that have plagued big-block racers for years. Each unit is in-house machined on precision CNC equipment to ensure the highest quality and to eliminate the need for expensive blueprinting.
WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.
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WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.