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Roush R2300 Phase 1 to Phase 2 Supercharger Upgrade Kit (05-09 GT)

Item 389812
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      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • Serious Power Upgrade
      • Upgrade from 475 to 550 HP
      • Upgrade from 435 to 500 ft. lbs.
      • Bolt-on 80mm Supercharger Pulley
      • Pulley Ratio: 2.1
      • Dual Fuel Pump Kit
      • Roush PCM Flash Voucher Card Included
      • Fits 2005-2009 GT Mustangs with a Roush Phase 1 Supercharger


      Much More Horsepower! Increase the power of your Roush R2300 Phase 1 supercharger from 475HP/435 ft-lb to an impressive 550HP/500 ft-lb with a Phase 1 to Phase 2 Supercharger Upgrade Kit. That's an increase of 75 horsepower and 65 lb-ft of torque that you'll feel immediately upon installation!

      Kit Includes. The Roush R2300 Phase 1 to Phase 2 Supercharger Upgrade Kit includes a new 80mm Bolt-on Pulley, 6-Rib Serpentine Belt, Dual Fuel Pump Kit, ROUSH PCM Flash Voucher Card and installation instructions.

      Upgraded ROUSH PCM Calibration. ROUSH® PCM calibration is a success of engineering that maximizes the power of the system. ROUSHcharger owners will receive a ROUSH® PCM Flash Voucher Card, which is used to obtain the specific calibration needed for your Mustang and requires ROUSH Diagnostic Tool (RDT) software and a J2534 Pass-Through device to upgrade your PCM (software and pass-through device not included).

      Application. This ROUSH Phase 1 to 2 Supercharger Upgrade Kit fits 2005-2009 GT Mustangs equipped with the 4.6L Modular V8 engine and a ROUSH Phase 1 TVS Supercharger installed.

      Technical Note. This ROUSH Phase 1 to 2 Supercharger Upgrade Kit is not legal for use in California or other states adopting California emission standards.

      Fitment: 2005 2006 2007 2008 2009 Details

      MPN# 421101

      CA Residents: WARNING: Cancer and Reproductive Harm -


      Customer Reviews (2)

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      Ratings Summary

      4.5 out of 5 overall rating from 2 customers

      • February 10, 2020

        4 2006 GT - Wayne01

        Phase 1 to Phase 2 supercharger

        Great service quick delivery. Item was as described

        Helpful (0)
      • December 18, 2016

        5 2008 GT - Jay


        This product is a bit pricey but definitely worth every penny if you're looking to take your stang to the next level

        Helpful (18)

      Questions & Answers (2 answers)

      2 Top Rated Questions

      Any need for internals upgrade for the phase 2 kit? Car is street driven...

      • lnternal upgrades can vary based on additional mods, tune, etc., we recommend speaking with your and/or tuner directly for recommendations.

      Helpful (0)

      Why wont this fit the 2010 GT? its the same engine as the 05-09 GT.

      • Unfortunately the phase 2 kit is not available for 2010 Mustang as it was discontinued. Due to some differences between the 2009 an 2010, this kit will not work.

      Helpful (0)
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      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) 80mm Supercharger Pulley
      • (1) 6-Rib Serpentine Belt
      • (1) ROUSH Flash Voucher Card
      • (1) Dual Fuel Pump Upgrade

      Tech Specs

      Will It Fit My Mustang

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