Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

KB HYP PISTON KIT SBC 400

$658.84

SKU: U00B KB139KTD.030

In Stock
In Stock
Ships by Jun 7
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Professional / shop required

Description

Keith Black Hypereutectic pistons are designed for high-performance Small Block Chevy 400 engines with a 4.155" bore, 3.750" stroke, and 5.700" rod length. They feature a flat-top design with 7cc and 2 valve reliefs, and a compression height of 1.433". This set includes 8 pistons made from a low-expansion 390 alloy, providing tighter piston-to-wall clearances.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB139KTD.030

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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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