Announcement

Collapse
No announcement yet.

2021 XT21 with 6.2l GDI Fuel Consumption

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 2021 XT21 with 6.2l GDI Fuel Consumption

    I've noticed a few comments throughout miscellaneous threads that discuss fuel consumption rate. But all the comments I found were primarily anecdotal evidence that lacked specificity. So I'd like to take this opportunity to discuss my observed rate of fuel consumption in a brand new 2021 XT21 equipped with the optional Ilmor 6.2l GDI.

    Because I'm still in the break-in period, these results are optimistic. This boat has only cruised the lake between 3000RPM and 3500RPM with a good amount of cool-down idle time. And I don't know for sure if the tank was filled before or after the manufacturer & dealer started/tested the motor. Nonetheless, here's the math starting with some basic specifications:
    • XT21 with two people and equipment: Approximately 5100lbs
    • XT21 tank capacity: 51 gallons
    • Current engine hours: 9.0hrs
    • Current fuel reading: 20% remaining

    51gal/100 = .51 gallons per percentage remaining
    .51gal * 20 units remaining = 10.2 gallons still in the tank
    51 starting gallons - 10.2 gallons remaining = 40.8 gallons of fuel consumed
    40.8 gallons used / 9 engine hours = 4.53 gallons consumed per hour

    So at the end of the day, an XT21 with the 6.2l GDI can cruise while consuming approximately 5 gallons per hour (I'm rounding up to compensate for the idle time mentioned above).

    Does anyone see a problem with my math? Do these results agree with your personal observations?

    UPDATE: See second page for more details. I now believe this combination is consuming approximately 4 gallons per hour.
    Last edited by oscilated; 04-09-2021, 10:01 PM. Reason: Updated Fuel Consumption to 35.5 Gallons
    -Oscilated

    2021 XT21 with 6.2GDI

  • #2
    Not sure about the math, but a 6.2 in a XT21 will be a BEAST!!! You will never lack for power.
    2017 NXT22, 2015 NXT20, 2007 X2, 2002 209

    Comment


    • #3
      We have a XT21 in production this. Let's see some pics of the new boat.
      Our 2014 X2 is Sold.

      Comment


      • #4
        Originally posted by SteveO View Post
        Not sure about the math, but a 6.2 in a XT21 will be a BEAST!!! You will never lack for power.
        To be honest, we purchased the upgraded motor primarily because it weighs less than the standard 6.0l MPI, despite having more power and being more fuel efficient. I love slalom skiing too much and wanted every advantage to reduce wave size and increase pull.
        -Oscilated

        2021 XT21 with 6.2GDI

        Comment


        • #5
          XT21 with 6.2

          We had this combination on our 2017. Your GPH looks about right. We loved the performance! A lot of smiles out on the lake with this. Great choice, congrats!
          Find us on Instagram @Bee_Boss_Surf

          Brynlee 7yrs, Boston 6yrs
          SoulCraft Team Riders



          2020 MC XStar white / Grey (Harley’s)
          2021 MC X22 white/ Kahuna
          2021 MC XStar Red
          2021 MC XT22. Yellow/Silver
          2020 MC XStar Blue
          2020 MC X24. Navy/Silver
          2020 MC XStar Red/Black
          2020 MC XT22 Red/black
          2019 MC XStar Blue/White
          2017 MC XT21 Black/Green
          2001 Calabria Pro V White/Yellow

          Comment


          • #6
            I have an xt21 with the 5.3L coming in about 15 days. I’ll try to update my performance once I have some hours. I’m hoping it’s better on gas than the 6.0l standard.

            Comment


            • #7
              Our 5.7 in the x2 was around 4.5 per hour
              Our 2014 X2 is Sold.

              Comment


              • #8
                ^osc, your math seems correct. Would guess your GPH consumption will improve post break in. What prop are you running?

                We get less than your threshold with x10 and 6.0L but are running high altitude with an aggressive prop, with lots of surf time too.

                Lastly, where the heck are your boat pics? Congrats and enjoy.

                Comment


                • #9
                  What gauge are you using to read your fuel level as in do you have the fuel management turned on?

                  My 2018 XT21 will read empty with 25 percent fuel in the tank with fuel management on. Apparently after reading some info about it here, MC leaves a nanny buffer on the fuel management that was not able to be changed.

                  I turned off the fuel management so that the analog tank sensor is used on my analog gauge, meaning I am pretty much empty at empty.

                  Now if you have dual electronic displays, I have no idea if that changes anything.
                  Originally posted by oscilated View Post
                  I've noticed a few comments throughout miscellaneous threads that discuss fuel consumption rate. But all the comments I found were primarily anecdotal evidence that lacked specificity. So I'd like to take this opportunity to discuss my observed rate of fuel consumption in a brand new 2021 XT21 equipped with the optional Ilmor 6.2l GDI.



                  Because I'm still in the break-in period, these results are optimistic. This boat has only cruised the lake between 3000RPM and 3500RPM with a good amount of cool-down idle time. And I don't know for sure if the tank was filled before or after the manufacturer & dealer started/tested the motor. Nonetheless, here's the math starting with some basic specifications:


                  • XT21 with two people and equipment: Approximately 5100lbs
                  • XT21 tank capacity: 51 gallons
                  • Current engine hours: 9.0hrs
                  • Current fuel reading: 20% remaining


                  51gal/100 = .51 gallons per percentage remaining

                  .51gal * 20 units remaining = 10.2 gallons still in the tank

                  51 starting gallons - 10.2 gallons remaining = 40.8 gallons of fuel consumed

                  40.8 gallons used / 9 engine hours = 4.53 gallons consumed per hour



                  So at the end of the day, an XT21 with the 6.2l GDI can cruise while consuming approximately 5 gallons per hour (I'm rounding up to compensate for the idle time mentioned above).



                  Does anyone see a problem with my math? Do these results agree with your personal observations?
                  Sent from my SM-G965W using Tapatalk

                  Comment


                  • #10
                    ^^^This is true. The senders are shorter than the tanks to protect the fuel pump from empty tanks. So "empty" really leaves several gallons in the tank, but keeps the pump cool and wet.

                    Comment


                    • #11
                      Originally posted by Black ‘n Green View Post
                      We had this combination on our 2017. Your GPH looks about right. We loved the performance! A lot of smiles out on the lake with this. Great choice, congrats!
                      Thanks!

                      Originally posted by [email protected] View Post
                      I have an xt21 with the 5.3L coming in about 15 days. I’ll try to update my performance once I have some hours. I’m hoping it’s better on gas than the 6.0l standard.
                      I would also expect the 5.3l GDI to be more efficient than the MPI motors.

                      Originally posted by dt37803 View Post
                      Our 5.7 in the x2 was around 4.5 per hour
                      Interesting. Isn't the 5.7l an MPI fuel delivery that uses the "older" GM Vortec pushrod motor? If so, I'm impressed with the numbers.

                      Originally posted by moosehead View Post
                      ^osc, your math seems correct. Would guess your GPH consumption will improve post break in. What prop are you running?
                      GPH should increase after break-in, but this first tank has seen quite a bit of idle time. So I'll be shocked if the GPH gets any better when we're actually using the boat instead of just cruising/idling.

                      Regarding the prop, I'm not sure. We're running whatever MasterCraft put on it

                      Originally posted by WolverineFW View Post
                      What gauge are you using to read your fuel level as in do you have the fuel management turned on?

                      My 2018 XT21 will read empty with 25 percent fuel in the tank with fuel management on. Apparently after reading some info about it here, MC leaves a nanny buffer on the fuel management that was not able to be changed.

                      I turned off the fuel management so that the analog tank sensor is used on my analog gauge, meaning I am pretty much empty at empty.

                      Now if you have dual electronic displays, I have no idea if that changes anything.
                      Dang it!!! I think you found a problem with my calculations. I have the dual dash and am using the electronic indicator with fuel management turned on. Based on your comment, I guess I have more than 20% actually left in the tank. Hmmm... Not sure how I can compensate to get a better calculation. Anyone have any ideas?
                      -Oscilated

                      2021 XT21 with 6.2GDI

                      Comment


                      • #12
                        Update:

                        We decided to fill up the tank today. The boat took 35.557 gallons (even though the fuel management system claimed 28.8 was needed to fill it up).

                        Recalculating my initial readings...

                        35.56 gallons used / 9.1 engine hours = 3.91 gallons consumed per hour

                        So maybe it's within reason to expect an XT21 with the 6.2l GDI to consume approximately 4 gallons of fuel per hour while operating with a mix of crusing and idling.
                        -Oscilated

                        2021 XT21 with 6.2GDI

                        Comment


                        • #13
                          Originally posted by moosehead View Post
                          What prop are you running?
                          I'm not sure if this is correct, but I took a picture of the center hub. It says:

                          OJ 15x16.25 MF WP 825 7/20
                          -Oscilated

                          2021 XT21 with 6.2GDI

                          Comment

                          Working...
                          X