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JE Pistons 258260 Forged Dome Piston Set Bore Alloy - 4.375 2618 8-Cylinder

Part of: JE Pistons Forged Dome Piston Set Bore

Other options in this family: JE Pistons 353906 JE Pistons 186235 JE Pistons 359152 JE Pistons 361278 JE Pistons 182027

Manufacturer

Picture for manufacturer JE Pistons

Part Number

258260
5 reviews
Sale Price

$1,096.99

Estimated ship date Sunday, November 15

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Product Details

JE Pistons 258260 is a high-performance forged piston set engineered from 2618 aluminum alloy for maximum strength and durability in demanding racing and performance applications. This 8-piston set features a dome crown design optimized for open chamber cylinder heads, with a 4.375-inch bore diameter, 1.395-inch compression distance, and 0.990-inch wrist pin diameter.

Key Features:

  • Application-specific forging process creates optimized, uniform crown thickness for consistent combustion chamber geometry
  • Contact reduction groove minimizes frictional drag between piston and cylinder wall for improved efficiency
  • Accumulator groove design increases top ring stability and sealing performance under high cylinder pressures
  • CNC-machined side relief with lower support band provides additional skirt strength and rigidity
  • Precision-honed pin bores ensure proper wrist pin fit and alignment
  • Double pressure-fed pin oilers maintain critical wrist pin lubrication
  • Wire locks included for secure wrist pin retention

Recommended ring set: J10008-4375-5. All JE Pistons are sold as precision-matched sets to ensure balanced rotating assembly. With over 60 years of proven performance in Chevy, Ford, Mopar, and Buick racing engines, JE Pistons continues to set the standard for forged racing pistons.

Products specifications

Block Height

9.78

Bore

4.375

Bore (in)

4.375 in.

Bore (mm)

111.125mm

CID

481

Comp Height

1.395

Comp Ratio @ 110cc

14.5:1

Comp Ratio @ 118cc

13.2:1

Comp Ratio @ 124cc

12.3:1

Compression Distance (in)

1.395 in.

Dome Volume

47

Gram Weight

641

Oversize

0.125

Pin Diameter (in)

0.990 in.

Piston Head Volume (cc)

-47.00cc

Piston Material

Forged aluminum

Piston Ring Thickness

1/16 in. x 1/16 in. x 3/16 in.

Piston Style

Dome, with two valve reliefs

Quantity

Sold individually.

Rod

6.385

Stroke

4

Wrist Pin Style

Press-fit or floating

Ringset Included

No

Add-On

J10008-4375-5

Oil Ring Thickness

0.188

Add-On

990-042-CS

Category Hierarchy

Pistons>Piston Kits

Piston Pin Wall Thickness

0.150

Top Compression Ring Thickness

0.064

Industry

Automotive

Engine

BIG BLOCK CHEVY

Out of Stock Message

Call for Availability

Compression Height

1.395

Piston Avg Wt

629

Piston Volume

47

Second Compression Ring Thickness

0.064

Cylinder Head

OPEN CHAMBER

Piston Head Type

Dome

Piston Pin Length

2.930

Piston Pin Material

5115

Piston Material

2618

Bore Diameter

4.375

Forging Type

Round

Add-On

990-2930-15-51S

Piston Pin Outside Diameter

0.990

Product Market

Domestic

Make

Chevrolet

Prop 65

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Piston Quantity

8

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Am happy with price, lower than anywhere else. Product is perfect and shipping was fast. Had to call because website was down while price increases were uploaded, cost an extra $20 but still worth the savings. Would definitely buy from again.

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Easy to order

Awesome customer service and very good pricing!

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