JE Pistons
JE Pistons BMW B58B30 Ultra Series Piston Set - 83mm Bore - 389617
- Catalog SKU
- jep389617
- Manufacturer part #
- 389617
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Product details
Product information
Overview
Ultra Series forged pistons from JE are the industry’s strongest, most fully featured pistons available off the shelf. Offered for BMW B58 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
These pistons utilize our dedicated Forged Side Relief (FSR) forging that was specifically designed to increase strength.
Features & Benefits
- 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.
- Contact Reduction: Reduce the amount of contact area against the cylinder wall when the piston "Rocks over". Contact reduction also serves to disrupt the flame travel into the crevice area causing a reduction in detonation.
- 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 BMW B58 Engines. To provide optimized performance durability
- Includes high-quality wrist pins, locks, and JE Pro Seal premium piston rings
- Made 100% in the USA
Application & fitment
Fitment has not been independently verified for your vehicle. Confirm the manufacturer application against your year, make, model, trim, and modifications before ordering.
Shipping & availability
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