Engines and Components› Pistons and Piston Rings

Kb pistons

KB Hypereutectic Flat Top Piston Set

$452.59

SKU: KB349-030

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Overview

The Kb pistons KB349-030 is a set of 8 hypereutectic pistons designed for a Ford SB 347 engine. These pistons feature a flat top design with a 4.030-inch bore size, 3.400-inch crankshaft stroke, and 5.400-inch rod length.
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The Kb pistons KB349-030 is a set of 8 hypereutectic pistons engineered for high-performance marine, drag race, circle track, street, or towing applications in Ford SB 347 engines. Constructed from a low-expansion 390 alloy with 16 percent silicon, these pistons allow for tighter piston-to-wall running clearance. They feature fully machined heads and valve reliefs, CNC machined pin bores for accuracy, and an accumulator groove to aid the compression ring seal. Additional features include machined oil returns, diamond-finished skirts, and mini grooves to reduce scuffing and overheating. The pistons have a flat top design with a 0cc volume, suitable for various compression ratios depending on cylinder head volume (12.2:1 with 55cc, 11.4:1 with 60cc, 10.8:1 with 64cc, and 10.2:1 with 69cc heads). Key specifications include a 4.030-inch bore size, 3.400-inch crankshaft stroke, and 5.400-inch rod length. The compression height is 1.090 inches, and the wrist pin size is 0.927 inches. The advertised piston weight is 428 grams, with a 107-gram wrist pin. These pistons are designed for use with a Ford 302 block and Ford Sportsman "N" heads, featuring a centered pin that is 2.5 inches long, with a spacer ring included. The OE deck height is 8.206 inches. Please note that the 1/16 x 1/16 x 3/16 rings are not included and must be purchased separately.

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

BrandKb pistons
Part NumberKB349-030
CategoryEngines and Components

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