STILLEN Nissan 370Z/350Z / Infiniti FX35, G35, G37, Q40, Q50, Q60 Standard Performance Lightweight Crank Pulley - 400338

The STILLEN Standard Performance Lightweight Crank Pulley is engineered to reduce rotating mass and improve engine responsiveness for Nissan and Infiniti performance vehicles. CNC-machined from 6061 aerospace-grade billet aluminum, this pulley replaces the heavy OEM steel crank pulley with a dramatically lighter design while maintaining factory belt routing, timing marks, and reliability.

By reducing parasitic drag and rotational inertia, the STILLEN crank pulley helps free up horsepower and sharpen throttle response without underdriving accessories. Designed with precision-broached keyways and stainless steel wear sleeves at all seal contact points, this pulley delivers long-term durability and performance. It is fully compatible with STILLEN supercharger systems and is specifically intended for dual throttle body engines.

Fitment:

• Nissan 350Z
• Nissan 370Z
• Infiniti FX35
• Infiniti G35
• Infiniti G37
• Infiniti Q40
• Infiniti Q50
• Infiniti Q60
• Fits RWD & AWD models
• Engine Requirement: Dual Throttle Body engines only
• Emissions Notice: Not for sale or use in California

Key Features:

• Standard-size lightweight crank pulley (no underdrive)
• CNC-machined from 6061 aerospace-grade billet aluminum
• Manufactured in-house by STILLEN for precision and quality control
• Maintains OEM timing marks and factory belt alignment
• Stainless steel sleeves at seal contact points for durability
• Precision-balanced for smooth high-RPM operation
• Compatible with STILLEN supercharger systems
• Significant reduction in rotating mass for improved throttle response

Technical Details / Performance:

• OEM pulley weight: 4.72 lbs
• STILLEN pulley weight: 1.32 lbs
• Weight reduction: Up to 80% lighter than stock
• Observed gains: Up to 10+ WHP (results may vary)
• Material: 6061 billet aluminum
• Replacement belt required: STILLEN #40338B
• Part number: 400338