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Vehicle Info NeededEAGLEPART NUMBER: 356-21203030
Eagle Big Block Mopar Competition Rotating Assemblies
$2,75499
Ships on 09/14/2026
Lowest Price Guarantee440 Block 8 Bolt Flange Competition Assemblies
- Competition Rotating Assembly -
Mopar 440
Stroke: 4.375
Disp. @ 4.350: 520
Rod Length: 7.100
Pistons: -8cc Flat Top
Rings: File Fit
Comp. Ratio 72cc/80cc/84cc: 12.6/11.7/11.3
Designed for Internal Balance - Flexplate/Flywheel and Balancer Not Included, Professional Machine Shop Balancing Required
Eagle Big Block Mopar Competition Rotating Assemblies offer the ultimate reliability and strength at an affordable price for the most demanding applications. These kits include an Eagle Forged 4340 Steel Crankshaft, Eagle H-Beam Rods, Mahle Forged Pistons, Hastings Rings and high-performance Clevite or King Bearings.
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Notes:
- Assembly part numbers that begin with “B” are balanced by Eagle and require no additional balancing. Part numbers that do not begin with “B” are unbalanced assemblies and must be balanced by a qualified machine shop before use.
- All kits are designed for internal balance.
- Mopar 400 "B" engines have a standard bore size of 4.340". Kits are available in .030" oversize only (4.375").
- Mopar 440 "RB" engines have a standard bore size of 4.320". Kits are available in .030", and .055" oversizes.
- Eagle Specialty Products reserves the right to substitute pistons due to availability.
Part TypeEngine Rotating Assembly Kit
Product LineEagle Big Block Mopar Competition Rotating Assemblies
BrandEAGLE
Part CategoryPerformance Parts
Crankshaft MaterialForged 4340 steel
Piston And Ring Oversize0.03 in (0.8 mm)
Main Bearing Undersize (Mm)Stock
Wrist Pin StyleFloating
Connecting Rod Beam StyleH-beam
Rod Bearing Undersize (Mm)Stock
Piston Ring Facing MaterialPlasmamoly
Piston StyleFlat top, with two valve reliefs
Assembly Lubricant IncludedNo
Piston Head Volume (Cc)6
Gaskets IncludedNo
Rear Main Seal Style2-piece
Main Bearing Undersize (In.)Stock
Crankshaft IncludedYes
Piston Rings IncludedYes
Bore (Mm)110.49
Actual Engine Cid521
Engine Stroke4.375 in (111.125 mm)
Connecting Rod MaterialForged 4340 steel
Pistons IncludedYes
Rod Bearing Undersize (In.)Stock
QuantitySold as a kit
Main Bearings IncludedYes
Engine BalanceInternal
Rod Bearings IncludedYes
Connecting Rods IncludedYes
Oil Pump IncludedNo
Camshaft IncludedNo
Timing Chain And Gears IncludedNo
BalancedNo
Piston MaterialForged aluminum
Cam Bearings IncludedNo
Part FitmentSemi Universal
Plastigage IncludedNo
Lifters IncludedNo
Bore4.35 in (110.49 mm)
Vendor Part Number21203030
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
