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Vehicle Info NeededLUNATIPART NUMBER: 638-BP429IN
4.250-2.750-2.200RL6.385 NO BL
$2,27399
Ships on 09/15/2026
Lowest Price Guarantee- 4.250-2.750-2.200RL6.385 NO BL
Pro Blower Seriesâ?¢; Crankshaft; Stroke 4.250 in.; Main Dia. 2.75 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
Weight80.0 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 BalanceExternal
Rod Bearings IncludedNo
Rear Main Seal Style2-piece
Balancer Bolt Thread Size (In.)3/4-16
Requires Narrow BearingsYes
Engine Stroke4.25 in (107.95 mm)
Vendor Part NumberBP429IN
Package Qty1
Package TypeEA
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