4.125" Bore x 4.000" Stroke Forged Piston Set

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Engines and Components› Pistons and Piston Rings

BTR

4.125" Bore x 4.000" Stroke Forged Piston Set

Name: 4.125" Bore x 4.000" Stroke Forged Piston Set
Brand: BTR
SKU: BTRCP-LS41251110-FT-8

$969.99

SKU: BTRCP-LS41251110-FT-8

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Overview

It features a 4.125" bore, 4.000" stroke, and is designed to work with a 6.125" rod. The pistons have a 3.0cc flat top volume.

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Manufactured from 2618 alloy, these pistons offer superior strength and durability, designed to withstand high performance demands. They are balanced to within +/- 1 gram for optimal engine balance and feature dual forced pin oilers, accumulator grooves, forged side relief, and lateral gas ports for improved ring seal. The included premium Total Seal AP ring set features a 1.2mm x 1.2mm x 3.0mm pack with 440B Stainless Steel tops and a C33 Face Coating, Taper Hook Groove Napier second rings, and a 3-piece soft-nitrided rail flex vent oil ring, making it suitable for severe duty applications. These pistons are designed for a 4.125" bore and a 4.000" stroke, and are compatible with 6.125" connecting rods. The flat top piston style offers a 3.0cc volume. Heavy wall .230" Chromoly wrist pins with wire locks are included, and the FEA-designed forging ensures tight tolerances. This set is rated to 2000hp. Please note that many aftermarket rods, including BTR's own 6.125" LS rod set, may require the small end to be narrowed by .080-.100" for proper fitment due to the piston's minimum pin boss span of 1.060". Carrillo & Bullet rods typically do not require this additional clearancing.

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

Brand	BTR
Part Number	BTRCP-LS41251110-FT-8
Category	Engines and Components

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