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Roush Phase 1 to Phase 2 Supercharger Upgrade Kit - 727 HP (15-17 GT)

Market Price $1,130.99 You Save 5% ($55.00)
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  • Item 390770

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    Features, Video & Details

    • Roush Phase 1 to Phase 2 Supercharger Upgrade Kit
    • Upgrade to 727 Horsepower and 610 lb-ft of Torque
    • Includes 80mm Pulley, NGK Spark Plugs and Plug & Play Digital Fuel Pump Controller
    • Roush PCM Flash Voucher Card Included
    • 3 Year / 36,000 Mile Limited Warranty on Roush Parts Only
    • Fits 2015-2017 GT Mustangs with a 670HP Roush Phase 1 TVS Supercharger Kit

    Review & Installation Video

    Review & Install Video

    More Horsepower and Torque! Increase the power and performance of your current 670 HP Roush R2300 Phase 1 Supercharger to an impressive 727 horsepower and 610 lb-ft of torque with a Phase 2 Supercharger Upgrade Kit.

    Kit Includes. The Roush Phase 1 to Phase 2 Supercharger Upgrade Kit includes a new 80mm S/C Pulley, a preset plug and play digital fuel pump controller, cooler range NGK spark plugs, ROUSH PCM Flash Voucher Card and installation instructions.

    Roush Performance Quality - Guaranteed. Roush is known for a rich tradition of excellent racing performance engineering at the highest level of OEM quality and design. This Supercharger upgrade kit features a 3 Year/36,000 Mile Parts limited warranty (ROUSH Supplied Parts Only).

    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). If you don't have access to a pass-through device, you have the option of sending your PCM back to Roush, where they will flash your PCM for an additional $100 fee.

    Application. This ROUSH Phase 2 Supercharger Upgrade Kit works with both manual and automatic 2015-2017 GT Mustangs equipped with the Coyote 5.0L DOHC 4 valve V8 engine and a ROUSH R2300 Phase 1 TVS Supercharger that produces 670 horsepower. This voids optional Roush limited powertrain/drivetrain warranties.

    Fitment: 2015 2016 2017 Details

    MPN# 421994

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (1) Preset Plug and Play Digital Fuel Pump Controller
    • (8) NGK Spark Plugs
    • (1) 80mm Supercharger Pulley
    • (1) ROUSH PCM Flash Voucher Card
    • Installation Instructions
    Installation Info
    Tech Specs
    Will it fit my Mustang?
    • GT - 15, 16, 17

    This Roush Phase 1 to Phase 2 Supercharger Upgrade Kit is specifically designed for 2015-2017 GT Mustangs with 670hp Roush TVS Supercharger Kit installed.

      Customer Photos (2) Submit Your Photo

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        Questions & Answers (13)

        5 Top Rated Questions

        do i need to get my pcm reflashed if i already have the 670 hp tune with this upgrade?

        • You will need to reflash your PCM as the calibration voucher for the upgrade will be included.

        Helpful (1)

        Do you think this will fit the 2018GT or are they different in the engine bay?

        Do u need anything else for this or u can just buy this and it will increase your horsepower

        • All parts to complete installation will be included. Please note that a Roush R2300 Phase 1 TVS Supercharger is required.

        Helpful (0)

        I have a 2015 mustang GT, I'm not a car guy and I want to know exactly what is this roush phase one to two is and how does it work? Thanks

        • This kit will allow you to upgrade the Roush Phase 1 supercharger to a Phase 2 which will provide better performance.

        Helpful (0)

        Will it pass CA smog?

        • This kit is CARB legal for the 2015-2016 models under CARB EO: D-418-29. It is not CARB legal for the 2017 model at this time.

        Helpful (0)
        Post Your Question
        8 More Questions
        Can any Ford dealer flash this or does it have to be a Roush certified dealer? 1 answer
        Does the upgrade decrease miles per gallon? 1 answer
        What’s the part number on the spark plugs? 1 answer
        Will my warranty be voided with the phase 2 upgrade kit? 1 answer
        Whats typical install time for a shop to install? 1 answer
        Will I be able to hear my blower after installing the phase 2 kit on my roush? I really miss the blower whine! 1 answer
        would i have to upgrade fuel injectors on my 2015 GT? 1 answer
        I have the 2015 Mustang gt with the ford racing supercharger installed on my car. I was wondering If the roush phase 2 supercharger upgrade kit will work with the ford racing supercharger. I know the supercharger was developed with Ford and Roush, however I have not seen any advertisement for the ford racing phase 2 upgrade. 1 answer

          Customer Reviews (8) Write a Review

          Overall Rating 4.8

          out of 5 stars

          Installation Time:Full Day

          Installation Cost:$100-$250

          • Performance Gain 4.5 4.5
          • Fit 5 5

          • 5/5

            Installation Time: Afternoon

            July 17, 2019

            Roush Phase 1 to Phase 2

            Install was easy and I would give it 1 out of 3 wrenches! I can feel the difference in power from the Phase 1 kit. This Phase 2 kit is incredible!


            Year: 2015 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Shop Install

            May 11, 2018

            Roush phase 2 kit

            Good product, no problems. Had to drive it home in the rain (first time). Drivability great, you can feel more power.


            Year: 2015 Submodel: GT

            Helpful (5)

          • 4/5

            Installation Time: Afternoon

            December 20, 2017

            Good product with one problem

            This is a nice kit for a fair price to push it over 700hp. Drivability is still very good and the power increase can be felt immediately. Install is very simple, HOWEVER, I did have an issue with the PCM flash. When using the Roush software, you are prompted to put in the PCM tear tag number. Well, 2016 and up Mustangs don't have the tear tag info physically on the PCM like 2015 and prior, and getting the info can be a huge PITA if you don't have FMC dealer access. This isn't a big deal, but something customers need to be aware of if doing the install themselves so they don't brick their cars until they can get ahold of Roush.


            Year: 2016 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $250-$500

            December 15, 2017

            Roush Phase 2 Supercharger Upgrade Kit

            This kit definitely improved the horsepower on my Roush!. Gof it at a great price during Black Friday.


            Year: 2015 Submodel: GT

            Helpful (7)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $100-$250

            June 09, 2017

            Roush Phase 1 to Phase 2 2015 Mustang GT

            Nice increase in power, runs great. Highly recommend a stronger clutch to take advantage of the horse power increase. I had a Mcleod RXT 1000 HP installed, great for street driving plus great performance. That Mustang is great, lots of fun.


            Year: 2015 Submodel: GT

            Helpful (8)

          • 4/5

            Installation Time: Afternoon

            February 03, 2017

            Phase 2

            20 Rear wheel horsepower gain....... Was hoping for a little more, but not bad!


            Year: 2015 Submodel: GT

            Helpful (10)

          • 5/5

            Installation Time: Afternoon

            June 23, 2016

            And the winner is?

            Nice upgrade, turned that GT into an animal, now suspension to keep the animal under control !!! Thank you American Muscle for such quick delivery, worth the wait!!!!' Capt. Mike


            Year: 2015 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Afternoon

            April 14, 2016

            Hellcat killer!

            Worth the buy. Installation wasn't much of a hassle, but I would recommend getting someone professional to do it.


            Year: 2015 Submodel: GT

            Helpful (7)

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