Eagle 2439375900A6 Forged 4340 Stroker Crankshaft for 1990-1992 Mitsubishi/Eagle

Vehicle Fitment

• 1990-1992 Eagle Talon (TSi, 4G63 2.0L, 6-bolt rear flange)
• 1990-1992 Mitsubishi Eclipse (GS, GSX, 4G63 2.0L, 6-bolt rear flange)
• 1990-1992 Plymouth Laser (RS, 4G63 2.0L, 6-bolt rear flange)

Fitment Notes

• 6-bolt rear flange requirement
• Designed for internal balance; external balance setups are not supported
• Bearing clearances must accommodate chamfered/narrowed bearing requirement
• Stock stroke 4G63 (89-92) to 100mm stroker crank; requires compatible rod/piston geometry
• Street legal status unconfirmed - marketed as race-only in some jurisdictions

Features

• Forged SAE 4340 steel construction for high strength and durability
• Non-twist forging with stress relieving and shot-peening for fatigue resistance
• Journals precision ground and micropolished (≤5 Ra) for smoother bearing operation
• .125" fillet radii on rod and main journals to reduce stress concentrations
• Nitrided surface finish for wear resistance
• Chamfered oil holes for improved oil flow
• Target bob-weight tolerance ±2% for balancing consistency
• Rated for high performance builds; commonly used in stroker applications up to ~1000 HP (with supporting parts)

Specifications

• Material: Forged 4340 carbon steel
• Stroke: 3.937 in (100 mm)
• Main journal diameter: 2.244 in
• Rod journal diameter: 1.771 in
• Rear flange: 6-bolt pattern
• Balance type: Internal
• Weight: approximately 37 lbs (varies by vendor)
• Minimum rod length required: ~5.900 in for proper geometry

Included Components

• 1x Eagle 2439375900A6 forged crankshaft

Product Description

The Eagle 2439375900A6 is a high-performance forged crankshaft designed specifically for 4G63 engine platforms in Eagle Talon, Mitsubishi Eclipse/GSX, and Plymouth Laser RS models from 1990 to 1992. By increasing the stroke from stock to 100mm (3.937"), this stroker crank delivers significantly more torque and power potential throughout the RPM range, making it ideal for serious build-ups and engine rebuilds where stronger bottom end capability is required.

Constructed from premium forged 4340 steel and featuring non-twist forging, shot-peening, and nitriding, this crank is built for strength and durability under high load and stress. It also incorporates large .125" fillet radii on both rod and main journals and polished surfaces to reduce wear and fatigue. Because of its internal balance design, it demands compatible components and careful balancing during assembly. Use of chamfered / narrowed bearings is required. This part is typically used in performance or racing applications; street legality may vary depending on local regulations. Fitment is confirmed through 1992; 1993+ or other engines are unconfirmed.