Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

1 SET KB231.STD/1 SET 4000BM8.STD

$624.04

SKU: U00B KB231KTM.STD

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Description

KB Series Hypereutectic 390 Alloy with 16% Silicon Pistons. T-6 heat treated with advanced machining features. Offers advantages in compression restricted classes due to lower conductivity alloy and reflective piston top, reducing oil temperatures and combustion heat/pressure loss. Tight clearances for quiet operation and reduced oil consumption. Includes lockrings and pins. Set of 8. Suitable for High Performance, Marine, Drag, Circle Track, Towing. Features CNC machined pin bores, Diamond Finished Skirts, Machined in Oil Returns, Accumulator Grove, Fully Machined head and valve reliefs, Mini Grooves, Triple Spiral Lock Rings.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB231KTM.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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