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JE LS7 Asymmetrical FSR Flat Top Forged Piston (J311985) J311985

JE LS7 Asymmetrical FSR Flat Top Forged Piston (J311985)

4.125" bore, 4.000" stroke, 6.125" rod length, -5cc dome volume
SKU: J311985
Contact for availability
$1,735.10 - $1,735.10
$1,735.10
$1,735.10 - $1,735.10
$1,735.10
+ GST
Stock Status: 🛑 Sold out — please contact for availability

LS7 4.125" PISTONS -5cc FLAT

4.125" bore, 4.000" stroke, 6.125" rod length, -5cc dome volume

Part Number: J311985

Hands down, the best forged piston for your high performance LS engine! Our Asymmetrical FSR (Forged Side Relief) forging is engineered for today’s high power normally aspirated and forced induction LS engines. The exclusive asymmetrical skirt maintains a larger skirt area on the heavily stressed major thrust side, while reducing friction with a smaller skirt on the minor thrust side. The result is a high strength, lightweight piston that outperforms the competition! Note: For applications over 800hp, a thicker wall wrist pin is recommended.

Includes:

  • Pin #927-2250-15-51C (106g) for use with 6.125 Rod Length
  • Round Wire Locks # 927-073-MW

Features:

  • Accumulator Grooves
  • Double Pin Oilers
  • Offset Wrist Pin

Piston Specification: