Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

1 SET KB122.STD/1 SET 4000BD8.005

$577.20

SKU: U00B KB122KTD.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 KB122KTD.STD is for SB Chevy 383 engines with a 4.000" bore, 3.750" stroke, and 6.000" rod length. It is a set of 8 flat-top pistons with 7cc volume and 2 valve reliefs, designed for high-performance applications. The pistons are made from a low expansion 390 alloy with 16% silicon for tighter piston-to-wall clearance. Compression Height is 1.130". Wrist pins and spiral locks are included, but piston rings are not.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB122KTD.STD

Videos

Engine Failure!? Watch if you are running Hypereutectic pistons!

Engine Failure!? Watch if you are running Hypereutectic pistons!
Keith Black Hypereutectic Piston Info (Ring End Gap)

Keith Black Hypereutectic Piston Info (Ring End Gap)
The Truth: Cast vs Hypereutectic Pistons - Which One Is Better? | Engine Building 101 |

The Truth: Cast vs Hypereutectic Pistons - Which One Is Better? | Engine Building 101 |
Cast vs Hypereutectic vs Forged Pistons | Whats the Difference?

Cast vs Hypereutectic vs Forged Pistons | Whats the Difference?
Installing Keith Black Pistons in the DZ292 Small Block Chevy #engine

Installing Keith Black Pistons in the DZ292 Small Block Chevy #engine
KB Pistons and Ring End Gap

KB Pistons and Ring End Gap

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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