Exterior Components› Body Panels and Components

United Engine & Machine Co

CHEVROLET 489 ROD 6.385 FLAT TOP +3CC 1V KB HYPER PISTON SET

$78.68

SKU: U00B KB284.100

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Description

The United Engine & Machine Co. KB284-100 pistons are a set of eight hypereutectic pistons designed for high-performance applications. They feature a flat top with a 3cc valve relief and a 1.270-inch compression height.

These pistons are engineered for marine, drag race, circle track, street, or towing builds, utilizing a low-expansion 390 alloy with 16% silicon for tighter piston-to-wall clearance. They include fully machined head and valve reliefs, triple spiral lock rings, CNC-machined pin bores, an accumulator groove, machined oil returns, and diamond-finished skirts.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB284.100

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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