Engines and Components› Crankshafts and Components

Eagle Specialty Products

4.000" Stroke LS Main 1-Piece Rear Main Forged Crankshaft

$1,062.99

SKU: EAG434740006100

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In Stock
Ships by Sep 9
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$100 Minimum Order
30 Days Return
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Overview

The Eagle Specialty Products crankshaft is a forged 4340 steel component designed for Chevrolet Small Block engines. It features a 4.000-inch stroke, LS main bearing type, and internal balancing. The crankshaft is nitrided for durability and micro-polished to a 3 r.a. or less for extended bearing life. It is designed for a 1-piece rear main seal and includes a 58-tooth reluctor wheel.
Show original supplier description
Eagle forged 4340 steel crankshafts offer maximum strength at an affordable cost. These cranks are constructed from certified 4340 steel using a non-twist forging process. They undergo a multi-stage heat treatment for enhanced strength and are then X-rayed, sonic tested, and fully nitrided for superior longevity. The journals are micro-polished to a 3 r.a. or better to maximize bearing life, and all journals feature a .125-inch filet radius for added strength, requiring narrowed bearings. This crankshaft is specifically designed for Chevrolet Small Block applications and features an internal balance, a 4.000-inch stroke, and a 6.125-inch or longer rod length. It utilizes an LS main bearing type, a 1-piece rear main seal, and comes equipped with a 58-tooth reluctor wheel. Please note that rod and main bearings are not included with this crankshaft, and it requires narrowed bearings for installation.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandEagle Specialty Products
Part NumberEAG434740006100
CategoryEngines and Components

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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