STM Under-Driven Alternator Pulley with Raised Guides for Evo 4-9 *Backorder ETA 05/2026*

Backorder:
As of 02/2026 we are out of stock. We are working on a batch with a rough estimated ETA of around May 2026. We will fill all backorders first when they do get completed, so get your order in if you need one!

The STM Evo 4-9 10% under-driven alternator pulley with raised guides was originally designed to help stop the belt from jumping off at high RPM. This new revision makes the pulley 10% under-driven and lighter than stock, which lightens the load on your alternator. Fits all Evo 4/5/6/7/8/9 models and works with OEM and stock replacement belts.

Vehicle Fitment:
CN9A 1996-1997 Evolution IV
CP9A 1998-2000 Evolution V VI
CT9A 2001-2006 Evolution VII VIII IX

Features:
• Billet Aluminum
• Hard Anodized to help resist corrosion
• Lighter than OEM
• 10% under-driven
• 10% less wear on your alternator
• Works with stock belts
• Raised belt guides
• STM Products are made in the USA!
• Lifetime Warranty on STM Parts to the original purchaser against manufacturing defects.

Purchase Includes:
(1) Pulley

Shipping Times:
Typically ships in 1-4 days.

Also Available:
STM Evo 7/8/9 Alternator