With a fully forged rotating assembly and a Dart block, this short block will with stand big power reliably.

Block Information:

• Dart Big M Sportsman 4 bolt main 2 piece rear main seal
• Bore/Stroke: 4.500" x 4.250"
• Displacement: 540ci
• Camshaft Bearings: Dura-Bond, installed and clocked to OEM position
• Freeze Plugs: Brass, installed and sealed
• Oil Galley Plugs: Installed and sealed

Rotating Assembly:

• Crankshaft: Manley 4340 forged
• Balance: Internally balanced (front+rear)
• Rods: Manley 4340 forged H beam 6.385" with ARP 8740 bolts
• Compression Ratio: 112cc= 10.9:1 / 118cc= 10.4:1 / 121cc= 10.2:1
• Pistons: 2618 forged dome +10cc with single valve relief
• Rings: Plasmamoly

 Recommended Components:

• Balancer: Internal balance
• Flexplate/Flywheel: Internal balance
• Head Gasket: .038" thickness or per application
• Oil: 10W30 Non synthetic for first 3000 miles
• Oil Filter: Wix or K&N per application

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

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