2022-Up RZR Pro R 4 Cylinder AA ECU Flash



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  • AA ECU flash for 2022-Up RZR Pro-R 4 Cylinder Models  **Requires ECU to be sent in for programming unless choosing to purchase ECU outright**
  • Works with all models including ones with Dynamix and/or Evap models.
  • Looking for the best/most badass ECU tuning available for your RZR Pro-R?  AA’s performance tunes are now available to gain horsepower and torque.  Through our advanced ECU tuning we are able to modify parameters correctly to gain you the power needed.  We are highly experienced in tuning RZR’s and this will show.
  • The Pro R uses a new Bosch MG1 ECU.  Currently no programmers like the PV3 are available and no ETA, so sending your ECU in for a bench flash is the only way to get a great tune.
  • Big horsepower gains depending on the level of tune/modifications (see below tune descriptions for more details)
  • Much quicker throttle response and power delivery giving a whole new feel to the vehicle
  • Throttle by wire limiters disabled
  • Fan on/off at 185 degrees Fahrenheit (Stock is 190) which is just above the thermostat opening temp.  The progressive fan also ramps up in quicker to keep you running cooler than OEM.
  • Speed limiter removed in low and high gears (Most will be able to run over 100mph!)
  • More throttle % in low gear and reverse
  • Rev limit at a safe 8800 RPM (stock is 8650).  Ideal peak RPM is 8200-8500 with the flash, but 8800 is for ramp up overshoot/top speed.
  • AA’s wicked timing curve is safe for the fuel used, but we do a much better job of finding timing limits for ramp up/more torque.  Many others simply focus on wide open throttle timing/fueling.
  • AA’s modified fuel curve will still get decent mileage cruising, but is corrected over the factory lean AFR when needed.
  • Level 1:  This tune can be run on a bone stock Pro-R on 91-93 octane fuel.  This tune adds +10-11 RWHP (15-16 crank horsepower) putting you at roughly 240 crank horsepower with just a flash!  We would highly suggest our clutch kit with this tune to help with belt grip and gain additional low to mid range power.  This tune can be run with an aftermarket exhaust without any issue, but our Level 2 tune is the best option for aftermarket exhaust as it’s slightly richer for more power.
  • Level 2:  This tune is developed for a Pro-R with aftermarket exhaust on 91-93 octane.  It has just a bit more timing and a bit more fuel over Level 1.  This tune adds +16 RWHP peak and a massive +19 RWHP at 38 MPH (This is gaining roughly +25 crank horsepower) putting you at roughly 250 crank horsepower with just a flash and exhaust!  We would highly suggest our clutch kit with this tune to help with belt grip and to help drive the extra power to the wheels.  Due to how these motors/tuning works, this tune should work with about any aftermarket exhaust, but was tested and designed with our AA slip-on exhaust (header now available).
  • Level 3: This is available for those with BC drop-in camshafts.  This tune has revised fueling for the cams, especially down low where we found hot starts to be an issue and extremely rich in the low to mid range power, then slightly leaner up top.  Level 2 will work with cams, but it will not run or start as good as with our Level 3 tune.  **NoteFor Level 3/cams We HIGHLY recommend upgrading to the HP Tuners RTD.  While our tunes have been proven to work great with our shop vehicle and many others, some may have idle issues that need a revised tune.  Higher lift camshafts are very finicky at idle.  If you were to have idle issues, with the HP Tuners RTD we can deploy revised tunes quickly and easily whereas with a simple ECU flash that is not an option – you would need to send your ECU back for a reflash.
  • Looking for race fuel tunes?  We were also, but unfortunately we found no real power increase by adding octane.  Certainly a little extra octane is never a bad thing to keep your ECU from pulling timing, but we tried various attempts to make more power with no results.
  • If you’re unsure if your Pro-R is an EVAP model or not, check your Emissions Control sticker located on the front driver’s side frame rail above the master cylinder. See pictures for location.
  • *** ECU MUST BE SENT IN FOR PROGRAMMING:  Aftermarket Assassins, 2348 75th Ave, Osceola, WI 54020  *** (If selecting option to purchase ECU outright, disregard shipping notes as we will ship a new flashed ECU to you)
    • Customer is responsible for shipping to AA, a shipping label is not included in the price
    • Programming turnaround will vary, but is normally 1-2 days.
    • Express ECU service for US main 48 states only.   We’ll send you a next day UPS label, and ship your ECU ONLY back via next day.  All other pats will be shipped ground unless otherwise specified/selected during order checkout.  Keep in mind we cannot guarantee same day programming or control UPS shipping times/delays.  We will do everything possible to turn the ECU around as fast as possible.
    • When the ECU arrives, we’ll read your stock file and keep a file folder for your stock/tune files. We’ll then flash with the correct AA tune.
    • If you ever need to go back to the OEM tune, we charge $95 which includes shipping back to you (shipping back for lower 48 US only).  Please contact us if you need to go back to your OEM tune. *Optional: Purchase ECU outright so going back to stock is as easy as re-installing your factory ECU*
    • ENSURE you INSURE your ECU for $700.  AA is not responsible for shipping delays or lost ECUs. While more expensive over Priority Mail or Fedex, UPS has been the most reliable carrier in our experience.
    • Follow this link for instructions on locating/removing ecu
    • The ECU is located behind the passenger (rear passenger if 4 seat) seat. Remove the top panel behind the seats, then remove the fabric panel to expose the ECU.  Remove the Torx bolts and ECU connectors.
  • Why AA tunes over others?  We have been tuning UTV’s with CVT clutches for a long time, longer than almost anyone in our field going back to the 800 RZR.  Tuning a CVT vehicle properly is not an easy task as you have so many variables at one time.  We spend the time to wheel dyno(with actual UTV tires) correctly per modification, and have advanced ECU calibration and clutching knowledge to do so. Every change in horsepower can result in us changing clutching several times. We also develop most of our supporting mods so we know everything works correctly, and build parts to fit the vehicles needs.  Lastly and honestly the most important; we then back up our results with real world data logging on local trails and our facility on 110 acres.  It’s this combination that truly makes the difference and why AA normally has a faster vehicle with the same or less rated tune horsepower.   We left nothing on the table on the Pro R bolt-on parts, if others claim more power/gains for the same mods use caution in believing it!
  • If you have any other needs in these tunes, or any concerns; please e-mail!
  • Oh… and get ready for your RZR to flat out rip!