Exterior Components› Body Panels and Components

United Engine & Machine Co

CHRYSLER 360 ROD 6.123 QUENCH HEAD +2.8CC 2V KB HYPER PISTON SET

$76.65

SKU: U00B KB373.030

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Non-Returnable Item
INSTALL DIFFICULTY
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Professional / shop required

Description

The United Engine & Machine Co KB373.030 is a set of 8 hypereutectic pistons designed for Mopar small block LA and Magnum engines. These pistons feature a 4.030 in. bore, a 3.580 in. stock stroke, and a 6.123 in. rod length. They have a step head design with two valve reliefs and a piston head volume of +2.80cc.

Constructed from hypereutectic aluminum, these pistons offer improved oil control and reduced blow-by. The wrist pin style is press-fit or floating, with a pin diameter of 0.984 in. The piston ring thickness is specified as 5/64 in. x 5/64 in. x 3/16 in.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB373.030

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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