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Engines and Components› Pistons and Piston Rings

Keith Black

Set of 8 Hypereutectic Pistons, 4.280-inch Bore

$587.11 $510.53 Save $76.58

SKU: KB400-030

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Overview

The Keith Black KB400-030 is a set of 8 hypereutectic pistons designed for Mopar B-Series engines. These pistons feature a 4.280-inch bore and 5/64 x 5/64 x 3/16-inch ring grooves.

Constructed from a high-silicon 390 aluminum alloy and heat-treated to T6 standards, these pistons are engineered for lightweight performance, offering improved throttle response and RPM changes. The pistons have a dome volume of +6.00 cc.
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The Keith Black KB400-030 is a set of eight hypereutectic pistons engineered for Mopar B-Series engines. With a 4.280-inch bore and specific ring groove dimensions of 5/64 x 5/64 x 3/16 inches, these pistons are designed to deliver enhanced engine performance. Crafted from a 390 aluminum alloy enriched with high silicon content, these pistons are heat-treated to meet T6 standards, resulting in a component that is approximately 30% stronger than standard aluminum pistons. Their lightweight design contributes to improved throttle response and quicker RPM changes, while their robust construction ensures durability under high compression and high-temperature conditions. Key race-ready features include strategically located upper compression rings, gas-accumulator grooves for optimal combustion control, drilled oil returns for enhanced lubrication, and spiral-lock retainer grooves for secure assembly. These pistons feature a dome volume of +6.00 cc, which is suitable for a variety of engine builds and compression ratio requirements. KB Performance Pistons are produced by UEM, a manufacturer committed to quality, operating under an ISO 9001:2015 certified Quality Management System.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandKeith Black
Part NumberKB400-030
CategoryEngines and Components
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Shipping

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