Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

6876 FORD 390/6.4L BIG BLOCK FE (V8) SILVOLITE CAST PISTON SET

$44.56

SKU: U00B 1139.030

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Description

The United Engine Machine 1139.030 is a .30 over piston designed for Ford 390 engines. It features a compression height of 1.66 inches (42.164 mm) and a piston ring thickness of 5/64 x 3/32 x 3/16 inches. This piston is part of the performance parts category and is listed as semi-universal fitment. The wrist pin is included, but pin lock rings are not.

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B 1139.030

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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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