GrimmSpeed Lightweight Performance Crank Pulley for 2004 Subaru WRX STI

Upgrading your crank pulley is a quick easy way to gain more engine response, reliability and power. The OEM pulley on most vehicles is heavy, unsightly and can be prone to failure. GrimmSpeed addresses all of these issues with this high performance lightweight aluminum crank pulley. By reducing rotational mass there is less parasitic drag on the engine, which leads to more power and response (easier revs). The pulley weight has been optimized to provide the perfect performance gain, without triggering false misfire CELs. To address reliability GrimmSpeed machines the pulley out of solid 6061 T6 aluminum and eliminated the rubber ring that is often the cause of pulley separation on OEM designs. The GrimmSpeed Lightweight Crank Pulley also has a precisely machined keyway and timing marks to make install and tuning a breeze.

Key Features:

• Lightweight design (about 3.5 lbs less than stock) provides faster engine response, improved acceleration, and more power!
• Factory fit for an clean and painless install.
• Weight optimized to prevent false CELs.
• Compatible with Gates Stretch Belt install tool (not included).
• Precision balanced and CNC machined from anodized 6061 T6 aluminum.
• Clear OEM timing marks for accurate tuning and install.