Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

1 SET KB229.STD/1 SET 3736AM8.STD

$572.56

SKU: U00B KB229KTM.STD

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Special Order
Ships in 4–6 weeks
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Keith Black Hypereutectic Piston Kit KB229KTM.STD is designed for high-performance applications in Small Block Chevrolet (SBC) 305 engines. These flat-top pistons feature a -5.5cc volume and 4 valve reliefs, with a bore size of 3.736 inches. Crafted from hypereutectic 390 alloy, they offer low expansion and tight piston-to-wall clearances. Key features include fully machined heads, Triple Spiral Lock Rings, and Diamond Finished Skirts for enhanced durability and performance.

Fitment

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB229KTM.STD

Videos

Fool proof installing pistons on rods of a Small Block Chevy

Fool proof installing pistons on rods of a Small Block Chevy
Cast vs Hypereutectic vs Forged Pistons | Whats the Difference?

Cast vs Hypereutectic vs Forged Pistons | Whats the Difference?

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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