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Vehicle Info NeededEAGLEPART NUMBER: 356-12042030
Eagle Chevy Small Block 400 Competition Rotating Assemblies
$3,20199
Ships on 09/14/2026
Lowest Price GuaranteeChevy Small Block 400 Competition Rotating Assemblies3.480" Stroke 6.250" Rods Forged Pistons
- Competition Rotating Assembly -
400, 2.65 Main
Stroke: 3.480
Disp. @ .030: 377
Rod Length: 6.250
Pistons: 3cc Dome
Rings: File Fit
Comp. Ratio 64cc/76cc: 11.0/9.6
Designed for Internal Balance - Flexplate/Flywheel and Balancer Not Included, Professional Machine Shop Balancing Required
Eagle Chevy Small Block 400 Competition Rotating Assemblies are designed to offer the ultimate strength and reliability at affordable pricing for the most demanding applications using a Chevy 400 small block. Kits include high-quality components including an Eagle Forged 4340 Steel Crankshaft; Eagle H-Beam Rods; JE or Mahle Premium 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.
- Kits are designed for internal balance.
- Chevy 400 standard bore size is 4.125", kits are available in standard bore, .020", .030", .040" and .060" oversizes.
- Eagle Specialty Products reserves the right to substitute pistons due to availability.
Part TypeEngine Rotating Assembly Kit
Product LineEagle SBC 400 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 StyleDome, with two valve reliefs
Assembly Lubricant IncludedNo
Piston Head Volume (Cc)-3
Gaskets IncludedNo
Rear Main Seal Style2-piece
Main Bearing Undersize (In.)Stock
Crankshaft IncludedYes
Piston Rings IncludedYes
Bore (Mm)105.537
Actual Engine Cid377
Engine Stroke3.48 in (88.392 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
Bore4.155 in (105.537 mm)
Vendor Part Number12042030
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
