Fuel Consumption vs. Speed - A semi-scientific study of Raptor Fuel Economy

Discussion in 'Ford SVT Raptor General Discussions [GEN 1]' started by TurboDog, Nov 28, 2010.

  1. TurboDog

    TurboDog Member

    Age:
    56
    Posts:
    1
    Likes Received:
    1
    Joined:
    Oct 19, 2010
    Fuel consumption for the Raptor has been discussed frequently here, but I haven't seen anyone post information from a designed study. I don't have the resources to conduct a true scientific study, but did just complete a 3,700 mile road trip from Boston to Kansas and back for Thanksgiving and decided to take the opportunity to do a "semi-scientific" study.

    My 6.2 Raptor had logged just over 4,700 miles when I began my trip, so probably wasn't completely broken in, but should be getting there. I started by "research" while driving through Indiana (yep, I was really bored ;)) with about 6,200 miles on the odometer.

    Experiment #1 - Miles per Gallon vs. Miles per Hour


    Objective: Determine relationship between ground speed and fuel consumption.

    Conditions: Overcast, 41 degrees, wind light and variable

    Method: For this "experiment" I recorded the MPG estimated by the Raptor's onboard computer at a given speed over a distance of 5 miles. Thanks to multiple construction zones I was able to evaluate speeds as low as 40 mph, and went as high as 75 mph on stretches of open road with light traffic. I completed multiple 5-mile sections at all speeds between 40 and 75 mph.

    I determined my speed using my Garmin 755T GPS (my speedometer reads about 2 mph low, so I relied on the Garmin for a more accurate measurement), and maintained desired speed during the experiment using cruise control.

    Results: View attachment 1326

    Miles per Gallon for the Raptor decreased with increasing speed (DUH), ranging from 24.6 MPG at 40 MPH to 14.3 at 75 MPH. I had expected that MPG would decrease faster as speed increased, but the onboard computer indicated otherwise. Whether this is real, or results from the way the computer calculates mileage I can't tell. Using linear regression analysis of the observed MPG/MPH data, I would estimate the fuel consumption of my Raptor at various speeds to be:

    MPH Estimated MPG
    40 24.6
    45 23.1
    50 21.6
    55 20.2
    60 18.7
    65 17.2
    70 15.7
    75 14.3

    The question now is, "how accurate is the Raptor's computer's estimate of MPG?" To answer this, I compared the MPG reported by the computer to what I would get by manually calculating mileage at each fill up based on gallons used divided by distance traveled.

    Experiment #2 - Computer MPG vs Hand Calculated MPG


    Objective: Determine relationship between the Raptors computer estimated MPG and hand calculated MPG.

    Conditions: Temps from 16 to 46 degrees, winds variable

    Method: For this "experiment" I reset the MPG reading on the Raptor's computer each time I filled it with gas, and then at the next fill up compared the computer's estimated MPG for that tank of gas to what I calculated using miles traveled (from the odometer) to gallons consumed (from the fuel pump reading). This data was collected while driving on 2 lane and interstate highways in IA, NE, KS, IL, IN, OH, MO, PA, CT and MA with very little city driving. Now that I am back in Boston I will collect data to compare MPG in stop and go city driving, and will report that later.


    Actual Computer
    MPG MPG
    15.7 15.6
    15.1 15.9
    15.9 16.2
    14.7 15.2
    15.8 16.1
    17.0 17.3
    16.2 16.5
    16.1 16.8
    16.4 16.9
    17.8 17.8

    16.1 16.4 Average

    As you can see, the computer tended to over estimate MPG by an average of about 0.3 MPG compared to "hand" calculated mileage. Much closer than I was expecting, and pretty darned good. The MPG I obtained given the speeds I was driving during these long runs compares closely to what I observed in "Experiment 1" over the 5 mile segments, so I am confident that the mileage reported in "Experiment 1" is pretty close to accurate.

    As they say, "your mileage may vary", but hopefully this will provide some perspective on what fuel consumption to expect from the Raptor.
     
    Jimster58 likes this.
  2. F150SVT

    F150SVT Full Access Member

    Posts:
    126
    Likes Received:
    1
    Joined:
    Oct 25, 2010
    Location:
    Otsego, MI
    Welcome to the website TurboDog! Great first post!

    I came up with similar mpg numbers at 65 and 75mph. I am suprised the Raptor actually got 24.6mpg at 40mph. Now if I could only drive 40mph on the freeway. Usually I am pushing 80mph. :mrgreen:
     
  3. MagicMtnDan

    MagicMtnDan FRF Addict

    Posts:
    7,682
    Likes Received:
    1,769
    Joined:
    Oct 28, 2011
    Location:
    Magic Mountain
    Welcome to the forum and thanks for sharing your research with us. Great post!

    You've illustrated clearly why my mileage is so poor. My freeway speed often exceeds your highest MPH :mrgreen:
     
  4. LVdezertdawg

    LVdezertdawg Full Access Member

    Posts:
    886
    Likes Received:
    80
    Joined:
    Jul 13, 2010
    Location:
    Henderson, NV
    Fantastic post and welcome to the board. Although most of my mph are under 60 but mpg is usually less than 10. Could have something to do with the sand rooster tails shooting from the wheel wells. Doing it in the dirt!!!!
     
  5. MagicMtnDan

    MagicMtnDan FRF Addict

    Posts:
    7,682
    Likes Received:
    1,769
    Joined:
    Oct 28, 2011
    Location:
    Magic Mountain
    For sure. I checked my MPGs yesterday after 2 days in the sand and dirt and it said 10.4 :thumbsup: Running in Off-Road mode with TC off and the motor at redline will do that.
     
  6. KaiserM715

    KaiserM715 Kaiser Söze Staff Member

    Posts:
    8,580
    Likes Received:
    3,082
    Joined:
    Aug 5, 2010
    Location:
    Houston, TX
    Welcome aboard!!

    I keep track of the mileage for every vehicle I own and so far my over all average calculated by hand is 13.0 mpg (mixed driving, mainly surface street commuting) versus 12.8 mpg as indicated by the computer. I have a little over 5k and mileage has steadily improved, so we will see what the next 5k has in store.
     
  7. MagicMtnDan

    MagicMtnDan FRF Addict

    Posts:
    7,682
    Likes Received:
    1,769
    Joined:
    Oct 28, 2011
    Location:
    Magic Mountain
    Kaiser, you need to drive more, faster, and do more offroading :mrgreen:
     
  8. KaiserM715

    KaiserM715 Kaiser Söze Staff Member

    Posts:
    8,580
    Likes Received:
    3,082
    Joined:
    Aug 5, 2010
    Location:
    Houston, TX
    I have a trip report coming up when I get my pics compiled. Dan, I wholeheartedly agree. But time and family commitments dictate otherwise most of the time, unfortunately.
     
  9. GR8PMKN

    GR8PMKN Full Access Member

    Age:
    50
    Posts:
    147
    Likes Received:
    6
    Joined:
    May 18, 2011
    Location:
    Texas
    Great Report TurboDog. My driving habits must be terrible. Gas on...Gas off I have had my Raptor for 2 months and 2000 miles now and at best it averages 10.9 MPG and I live in Kansas. Drove it to OKC and back about 180 miles each way from where I live on I-35 running 80-ish all the way down and back and still only averaged 11.2 MPGs on the long open road. But I see it as getting better mileage than the H2 (7 to 9 MPG's) it replaced. Anyway welcome to the group

    Rick
     
  10. Nv Guy

    Nv Guy Full Access Member

    Posts:
    840
    Likes Received:
    261
    Joined:
    Feb 16, 2011
    Location:
    Nor Nv
    Here is what I have found:

    Comp Measured
    15 14.37
    14.1 13.88
    16.2 15.51
    16.8 15.38
    17.5 17.02
    15 14.69
    16.7 15.97
    16.4 15.68
    15.7 14.75
    17.1 17.58
    15.1 14.29
    16.5 15.93
    15.8 15.15
    16.4 16.44
    16.5 15.9
    16.5 16.17
    16.4 15.71 80 MPH run
    14.8 14.21 4WD @ 30-40 MPH

    16.02 15.47 Overall Average
    My finding are pretty close to T/D, in that the computer seems to over estimate the mileage, but that could be due to my simply adding a little more fuel to the tank.
    Most of my mileage tends to be 70% freeway, remainder being in town. Not nearly enough off road! (Gotta work on that).
    I have found that running over 70MPH tends to really hurt the mileage, as does running in 4WD @ 35-40 MPH in the snow.
     

Share This Page