JE Pistons Ultra Series 4G63 85.5mm Bore 10.0:1 CR Set of 4 Pistons (361291) - EVO 8/9

JE Pistons Ultra Series 4G63 85.5mm Bore 10.0:1 CR Set of 4 Pistons, part number 361291, made to fit the Mitsubishi EVO 8/9.

Ultra Series forged pistons from JE are the industry’s strongest, most fully featured pistons available off the shelf. Offered for Mitsubishi 4G63 Engines. Ultra Series Pistons feature JE’s proprietary Aligned Grain Flow forging technology providing next-level tensile strength ideal for the extreme cylinder pressures of power adder engine builds. Equipped with the following custom level features

• Accumulator Groove: A specialty groove between the top and second ring provides added volume for blow-by gases. This helps reduce pressure between the rings, improving top ring seal and minimizing ring flutter at high cylinder pressures.
• Lateral Gas Ports: This process mills slots into the top of the top ring groove and provides a pathway for combustion pressure to get behind the top ring. Resulting in increased ring seal and is most common in circle track applications.
• Thermal Crown: Applied to the piston crown, this thermal barrier coating reflects heat back into the combustion chamber to improve exhaust gas velocity and scavenging while reducing heat transfer to help extend piston life.
• JE’s proprietary Aligned Grain Flow forging technology providing next-level tensile strength ideal for the extreme cylinder pressures of power adder engine builds.
• Pin Fit: The pin bore is precision honed to attain an exact pin clearance. Clearances typically range from .0003 to .0010 between the wrist pin and pin bore.
• Skirt Coat: Skirt Coat reduces friction and wear on piston skirts and cylinder walls while simultaneously reducing operating noise
• Smooth Crown Finish: Deburs all areas around the valve pocket and dome area, to reduces stress risers and prevent hot spots.
• Designed specifically for Mitsubishi 4G63 Engines. To provide optimized performance durability

Fitment

• JE Pistons Ultra Series Mitsubishi EVO 7-9 4G63 85.5mm Bore 10.0:1 CR Set of 4 Pistons

Product details

• Brand: JE Pistons
• Part number: 361291
• Category: Engine Components / Piston Sets - Forged - 4cyl
• Shipping weight: 6 lb
• Not CARB approved. Not legal for sale or use in California on pollution-controlled vehicles.
• California Prop 65 warning applies to this product.

Check the fitment against your car before ordering. If you are not sure it fits, send us a message with your year and trim.

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