inc. GST

SKU: J312025

BRAND: JE Pistons

LS2 Asymmetrical FSR Dish Top Forged Piston
4.005" bore, 3.622" stroke, 6.125" rod length, -16.6cc dome volume

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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.


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


  • Accumulator Grooves
  • Double Pin Oilers
  • Offset Wrist Pin

Piston Specification:

  • Bore Diameter: 4.005
  • Compression Height: 1.304
  • Compression Ratio with 64cc chamber volume: 9.3
  • Compression Ratio with 68cc chamber volume: 9.0
  • Compression Ratio with 70cc chamber volume: 8.8
  • Piston Volume: -16.6
  • Cylinder Head: LS 12 DEG/15 DEG COMBO VR
  • Piston Pin Outside Diameter: 0.927
  • Piston Pin Length: 2.250
  • Piston Pin Material: 5115
  • Ringset Included: No
  • Top Compression Ring Thickness: 0.048
  • Second Compression Ring Thickness: 0.06
  • Oil Ring Thickness: 0.1175
  • Piston Material: 2618
  • Forging Type: FSR
  • Piston Avg Weight: 425
  • Pin Wall Thickness: 0.170
  • Piston Type: Dish

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