Dart Big M Sportsman Chevy Big Block Iron Block – 4.600 in. Bore, 10.200 in. Deck (31223654)
Dart engineered the Big M to be the strongest, most reliable, and easiest to build big block on the market. The Dart Big M2 is designed from the ground up as a true racing engine block which can be used with standard off the shelf big block components. The Big M2 is cast from premium high strength Iron and beefed up in all the critical areas. A competition oiling system ensures adequate lubrication to the main bearings at high RPM.
Standard 9.800” and tall 10.200” deck heights; Standard 4.250”, 4.500”, 4.560” or 4.600” bore sizes with siamesed extra thick cylinder walLS2 to resist cracking and improve ring seal (minimum .300” thick with 4.625” bore); Uses +.300” tall Gen VI style lifters. Modification for Gen IV style available; 4-bolt main bearing caps in Ductile Iron have splayed outer bolts for extra strength; True priority main oil system 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; Lifter valley head stud bosses prevent blown head gaskets; Dual oil pan bolt patterns fit standard and notched oil pans; Parts kit sold separately
Order Processing Time:
Orders are typically processed within 24-48 hours after the order has been placed.
Custom or special order items may take longer to process, typically 3-5 business days depending on the product and customization required.
Shipping Methods:
Standard Shipping (3-7 business days - location dependent)
Express Shipping (1-2 business days- location dependent)
Packaging:
All parts are securely packaged to better prevent any damage during transit. Fragile or high-value parts will be packaged with additional protective materials, such as bubble wrap or foam padding.
Shipping Rates:
Shipping rates vary based on the size, weight, and destination of the package. You can view the estimated shipping costs for your order during the checkout process before placing your order.
Order Tracking:
Once your order has been shipped, you will receive an email with the tracking number and carrier information. You can also track your order status by logging into your OCDiesel account.
USA Shipping:
We ship to the USA! (Except California) Please note that USA shipping rates and delivery times may vary based on destination. Customers are responsible for any customs fees, import taxes, or additional charges that may apply.
Not all products are stocked in-house. To ensure you receive your desired items promptly, please check for availability before placing your order. Some products may be backordered due to high demand or supply chain constraints, which could result in longer delivery times.
We strive to keep our inventory updated regularly, but availability can change quickly. For the most accurate information, contact the OCDiesel customer service team using either this link, or the chat bubble on the bottom right of this page.
Most items are eligible for return within 30 days of shipping, provided they are unused, in original manufacturer packaging, and in resalable condition. All returns & cancellations are subject to restocking and cancellation fees.
Returns must include a Return Authorization Number (RA #) and be shipped with tracking. Return shipping costs are the responsibility of the customer.
Custom/special orders, electronics, and digital goods are final sale—no returns, refunds, or exchanges.
For full return instructions, fee details, and conditions, click here.
