Engines and Components› Pistons and Piston Rings

AutoTec

4.185in Bore Forged Piston Set

$766.00

SKU: 1000586

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Overview

The AutoTec Oldsmobile 455 Forged Piston Set is a high-performance internal engine component designed for the Oldsmobile 455 engine. This set features flat-top pistons with two valve reliefs, a 4.185-inch bore, and a 4.250-inch stroke. Constructed from 4032 low-expansion, high-silicon aluminum alloy, these pistons are built for street/strip applications.
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The AutoTec Oldsmobile 455 Forged Piston Set (Part #1000586) is engineered for enhanced performance in Oldsmobile 455 engines. These pistons are crafted from a forged 4032 low-expansion, high-silicon aluminum alloy, offering excellent durability and suitability for street and strip applications. The set includes flat-top pistons with two valve reliefs, designed for a 4.185-inch bore and a 4.250-inch stroke. Key specifications include a compression height of 1.750 inches, a wrist pin size of 0.980 inches, and CNC-machined ring grooves that accept 1.5mm top ring, 1.5mm second ring, and 3.0mm oil ring sizes. The pistons also feature diamond-turned skirts for reduced friction. Compression ratios vary based on combustion chamber volume: 12.3:1 with 72cc chambers, 11.3:1 with 80cc chambers, and 10.6:1 with 87cc chambers. This set is sold as a set of 8 pistons and comes with pin fit, wire locks, broached pin oilers, and accumulator grooves. Please note that rings are sold 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

BrandAutoTec
Part Number1000586
CategoryEngines and Components
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Shipping

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