Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

KB HYP PISTON KIT SBF 331

$593.36

SKU: U00B KB355KTD.060

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 Ford Small Block 331 (SBF 331) engine builds. They feature a low expansion 390 alloy with 16 percent silicon, fully machined head and valve reliefs, triple spiral lock rings, and CNC machined pin bores. Key specifications include a 4.060-inch bore, 3.250-inch stroke, 10cc dish, and a compression height of 1.170 inches.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB355KTD.060

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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