LS ASYM FT 3.900 STRK

Name: LS ASYM FT 3.900 STRK
Brand: JE Pistons
SKU: J001 323978
Price: 1017.77 USD
Availability: InStock

$1,017.77

SKU: J001 323978

In Stock

Ships by Jun 8

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Non-Returnable Item

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Professional / shop required

Description

JE Pistons' 323978 is a set of 8 GM LS Asymmetrical FSR (Forged Side Relief) flat-top pistons designed for custom engine builds. These pistons feature a 4.000" bore, 3.900" stroke, and 6.125" rod length, accommodating popular stroke and rod combinations while preventing reluctor wheel clearance issues. They are machined for 1.2mm, 1.5mm, 3.0mm rings and include 12° & 15° valve pockets, accumulator grooves, double pin oilers, and an offset wrist pin. This set is suitable for Chevy LS Gen III/IV engines, specifically for modified engine specifications rather than direct OEM replacement.

Fitment

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Specifications

Brand	JE Pistons
Part Number	J001 323978

Videos

JE Pistons Asymmetrical Design Overview

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Piston Coatings 101: Which is the Right One for You?

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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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