Engines and Components› Engines, Blocks and Components

Mopar

SB Chrysler 360/408 Rotating Assembly Kit

$1,852.95

SKU: ESP-20508

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In Stock
Ships by Aug 6
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Description

The Eagle 20508 SB Chrysler 360/408 Street Strip Rotating Assembly is designed for pump gas street engines capable of producing up to 700 horsepower without power adders. This kit includes an Eagle cast steel crankshaft with a 4.000 stroke and Eagle forged 5140 steel "SIR" I-Beam rods featuring 3/8" ARP 8740 rod bolts. The assembly comes with forged Mahle pistons that have a -28cc dish design, paired with a performance ring set. It also includes performance rod and main bearings and a 2-piece rear main seal. The kit is sold as a non-balanced assembly, requiring internal balancing to be performed prior to installation. An optional balanced kit is available (Part number B20508).

MIA's Description

The Eagle 20508 is a SB Chrysler 360/408 street strip performance rotating assembly kit. It features a cast steel crankshaft with a 4.000 stroke and Eagle 6.123 I-beam rods. The kit includes Mahle forged -28cc dish pistons, a 2-piece rear main seal, and performance rings and bearings. This assembly is not internally balanced and requires balancing before installation.

Fitment

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Specifications

BrandMopar
Part NumberESP-20508
CategoryEngines and Components

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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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