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- STROKE-MAIN-PIN NO BAL 4.125-
Pro Seriesâ?¢; Crankshaft; Stroke 4.125 in.; Main Dia. 2.750 in.; Pin Dia. 2.2 in.; Rod Length 6.385 in.; Chevrolet Big Block V8;
Part TypeCrankshaft
BrandLUNATI
Package Height10.0
Package Width10.0
Package Length32.0
Weight88.0 PG
Part CategoryPerformance Parts
Crankshaft MaterialForged 4340 steel
Rod Journal Diameter2.2 in (55.9 mm)
Main Journal Diameter2.749 in (69.825 mm)
LightenedYes
QuantitySold individually
Crankshaft Snout StyleStandard
Main Bearings IncludedNo
Engine BalanceInternal
Rod Bearings IncludedNo
Rear Main Seal Style2-piece
Balancer Bolt Thread Size (In.)1/2-20
Requires Narrow BearingsYes
Part FitmentSemi Universal
Engine Stroke4.125 in (104.775 mm)
Vendor Part NumberBU421INLUN
Package Qty1
Package TypeEA
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