Engines and Components› Pistons and Piston Rings

Eagle Specialty Products

Rotating Assembly Kit

$2,309.97

SKU: EAG12503030

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

The Eagle Specialty Products EAG12503030 is a rotating assembly kit for Small Block Chevy engines. It features a 407 CID displacement, a 3.750-inch stroke, and a 4.155-inch bore.

This kit includes a forged crankshaft, forged pistons, and 6.000-inch H-beam connecting rods. Eagle Specialty Products is known for its quality engine parts, using state-of-the-art equipment and skilled craftsmen.
Show original supplier description
The Eagle Specialty Products EAG12503030 is a rotating assembly kit designed for Small Block Chevy engines, offering a robust solution for performance builds. This comprehensive kit includes a forged 4340 crankshaft and forged pistons, ensuring durability and reliability under demanding conditions. The assembly is designed with a 3.750-inch stroke and a 4.155-inch bore, resulting in a 407 cubic inch displacement. Complementing the crankshaft and pistons are 6.000-inch H-beam connecting rods, known for their strength and suitability for high-performance applications. Eagle Specialty Products emphasizes quality, utilizing advanced equipment and skilled technicians to produce engine parts that meet the standards of respected engine builders. Their commitment to quality control ensures that each component is ready for challenging applications. This rotating assembly kit is intended for serious performance applications. It is important to note that the assembly must be balanced by a qualified machine shop before installation and use.

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 NumberEAG12503030
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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