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HKS PULLEY UPGRADE KIT - Black Ops Auto Works
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HKS PULLEY UPGRADE KIT

HKS
HKS12002-KK001
4957266620069
Superchargers
Out of stock
$ 550.00
FREE Ground Shipping!

SKU: 12002-KK001 | UPC: 4957266620069

HKS Pulley Upgrade Kit for 2004-2021 Subaru WRX STI

The HKS Pulley Upgrade Kit transforms supercharger performance on Subaru WRX STI models from 2004 to 2021 equipped with HKS GT2 Supercharger. This kit features a smaller drive pulley that spins the supercharger faster for higher boost levels and substantial horsepower increases. Direct bolt-on design ensures seamless integration and reliable power delivery on the track or street.

Key Features

  • 20% Smaller Pulley Diameter: Increases supercharger RPM by 20 percent raising boost from 6 psi to 10 psi for immediate power gains up to 50 whp
  • Billet CNC Aluminum Construction: Lightweight durable material resists wear and maintains balance at high speeds
  • Complete Kit Contents: Includes pulley belt and hardware for straightforward replacement without additional parts
  • Direct Fit for HKS GT2: Engineered exclusively for HKS Supercharger Kit 12000-KK001 on EJ257 engines
  • Dyno Tested Results: Verified gains in torque and horsepower across 4000-7000 RPM range

Product Notes

  • Requires existing HKS GT2 Supercharger installation
  • Monitor boost levels after install to prevent overboost damage
  • Special order item ships within 3-5 business days

Installation Notes

  • Professional installation recommended.
  • Remove stock supercharger pulley using HKS pulley tool set
  • Compatible with OEM belt tensioner no modifications needed

This Part Fits

Year Make Model Submodel
2004-2007 Subaru Impreza WRX STI All (EJ257)
2008-2014 Subaru Impreza WRX STI All (EJ257)
2015-2021 Subaru WRX STI All (EJ257)

Why Choose HKS?

  • Motorsport proven in Super GT and rally championships
  • 50 years of turbo and supercharger expertise
  • JDM precision manufacturing for exact tolerances

Frequently Asked Questions

  • Q: Will this kit fit my 2017 STI with HKS supercharger?
    A: Yes fits all 2004-2021 WRX STI models with HKS GT2 Supercharger Kit 12000-KK001 and EJ257 engine
  • Q: What material is the pulley made from?
    A: High-strength billet 6061 aluminum CNC machined for balance and longevity
  • Q: What is the warranty and install time?
    A: HKS 1-year limited warranty 1-2 hours install time with basic tools and pulley puller

Shipping & Handling

  • Method: UPS Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Compact protective box 8 x 6 x 4 inches
  • Weight: 1.65 lbs

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