JE LS1 Extreme Duty Asymmetrical FSR Flat Top Forged Piston (J321240)

J321240 - LS1 3.905" PISTONS -2cc DISH

3.905" bore, 3.622" stroke, 6.098" rod length, -2cc dome volume

Part Number: J321240

We have redesigned and expanded our GM LS1 series product lines! These new pistons utilized our dedicated Forged Side Relief (FSR) forging that was specifically designed for high output GM LS1 series engines. In addition we have found ways to reduce weight and maintain the durability needed for both street and racing use. Lightweight and extremely durable, these pistons are machined for 1.5mm, 1.5mm, 3.0mm rings. Wrist pin upgrade recommended above 800hp.
Includes:
Pin #945-2250-15C (105g)

Round Wire Locks # 927-073-MW

Features:

High strength FSR forging
Accumulator Grooves
Double Pin Oilers
Offset Wrist Pin
Piston Specifications

Make: CHEVROLET
Engine: CHEVROLET LS GEN III/IV
Bore Diameter: 3.905
Compression Height: 1.340

Compression Ratio with 64cc chamber volume: 10.4

Compression Ratio with 66cc chamber volume: 10.2

Compression Ratio with 72cc chamber volume: 9.6

Piston Volume: -2
Cylinder Head: LSX/L92 12 DEG
Piston Pin Outside Diameter: 0.945
Piston Pin Length: 2.250

Piston Pin Material: 5115
Ringset Included: No
Top Compression Ring Thickness: 0.06
Second Compression Ring Thickness: 0.06
Oil Ring Thickness: 0.1175

Piston Material: 2618

Forging Type: FSR
Piston Avg Weight: 436

Pin Wall Thickness: 0.150
Piston Type: Flat