Engines and Components› Pistons and Piston Rings

JE Pistons

LS ASYM FT 3.900 STRK

$1,017.77

SKU: J001 323985

In Stock
In Stock
Ships by Jun 8
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Professional / shop required

Description

JE Pistons 323985 FSR Asymmetrical Flat Top Pistons are forged in the USA from 2618 aluminum for high tensile strength. Features proprietary Forged Side Relief (FSR) design for reduced friction, power loss, and weight. Skirt coating may reduce friction and wear. Accumulator groove helps improve ring seal. Designed for GM LS engines requiring a 4.080 in. bore, 3.900 in. crankshaft stroke, and 6.125 in. rod length. Compatible with LS3 408 engine builds.

Fitment

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandJE Pistons
Part NumberJ001 323985

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Buy with Confidence

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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