Engines and Components› Crankshafts and Components

Eagle Specialty Products

4.000" Stroke Small Block Mopar Crankshaft

$480.21

SKU: EAG103404000

In Stock
In Stock
Ships by Sep 9
Free Shipping over $200
$100 Minimum Order
30 Days Return
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Overview

It features a 4.000-inch stroke and internal balancing for smooth operation. This crankshaft is engineered with a 2-piece rear main seal for secure sealing.

This component is built for specific Mopar small block applications, including the 318 and 340 engines. It has a main journal diameter of 2.500 inches and a rod journal diameter of 2.125 inches. The crankshaft is not lightened and does not require narrow bearings.
Show original supplier description
The Eagle Specialty Products 103404000 is a cast steel crankshaft engineered to be a dependable and cost-effective solution for engine builds. Each crankshaft undergoes rigorous inspection for dimensional accuracy and stroke precision. To enhance efficiency and reliability, it features a journal finish of 6 R.A. or less and a target bob weight tolerance of +/- 2 percent, facilitating easier balancing. This crankshaft is specifically designed for Mopar Small Block engines, compatible with 318 and 340 cubic inch displacements. It offers a 4.000-inch stroke and features internal balancing for optimized performance. The design includes a 2-piece rear main seal style for secure sealing. Key specifications include a 2.500-inch main journal diameter and a 2.125-inch rod journal diameter. It is important to note that this crankshaft is not lightened and does not require narrow bearings. Rod and main bearings are not included. This particular model is recommended for use in pump-gas, naturally-aspirated, non-competition road cars, offering a solid foundation for street-driven performance vehicles.

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 NumberEAG103404000
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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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