Exterior Components› Body Panels and Components

United Engine & Machine Co

KB HYPER PISTON CHEVY 489 ROD 6.135 CC SOLID DOME 17CC 1V OR CHEVY 489 ROD 6.

$73.03

SKU: U00B KB397.STD

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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Professional / shop required

Description

The United Engine & Machine Co KB397.STD is a set of hypereutectic pistons designed for Chevrolet Big Block V8 engines with closed chamber heads. These pistons feature a solid dome with a single valve relief and are constructed from hypereutectic 390 alloy with 16% silicon, heat-treated to T6 standards.

The KB397.STD pistons have a 4.250-inch bore and a 4.250-inch stroke, suitable for use with a 6.135-inch connecting rod, resulting in a 482ci displacement. They include press-fit or floating wrist pins and triple spiral lock rings.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB397.STD

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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