Consumer Reports MPG Result For 2013 Fusion & C-Max Hybrids!

If he drives under 62 mph, I wonder how the two numbers would match up.

 

It is impossible to get useful data from this video because there is no way to calculate the inertial losses.
Your profile indicates you live in Florida where I know there are many, relatively flat, interstates. Find a stretch between two clover-leaf exits about 10 miles apart and conduct a series tests:

• 50 mph - both ways reach and set cruise control and then reset trip meter, record the MPG and miles for each pass, you need two in opposite directions to take out wind and any latent elevation changes.
• 60 mph - same as above
• 70 mph - same as above
• 80 mph if it is not a speeding and traffic risk - same as above

Now find an access road that parallels the interstate without traffic lights. Perform the same set of tests:

• 40 mph - same as previous
• 30 mph - same as previous test

Bring the raw data here for both cars and/or put into a spreadsheet and share. Note the weather and only use 'dry' condition.

Otherwise, you might as well whistle Dixie in front of a camera for all the good it will do.

Bob Wilson

 

Bob, I think it is a video from YouTube, not necessary one made by Sergiospl.

 

That makes sense. My apologies as it looked like this was something of your making. Perhaps you can find the author and invite them to come here?

If there are any C-MAX owners who are really interested in their vehicle performance then generate a table or graph showing MPG vs mph. That is the first step to understanding what is going on.

Dragging in videos doesn't help . . . unless it is possible to make a graph from the frames that has some credibility. That video was useless for that purpose.

Bob Wilson

 

+1

Yes YMMV and its tough to model from youtube.

The only data point that seems real on the c-max is motor trend got 34 mpg on a 75 mph cruise control loop, they try to measure gps distance and actual fuel consumed instead of mpg meter in the car. That is probably indicative of mileage falling rapidly at higher speeds. The c-max's cda is about 30% higher than the prius. What does your chart read at 75 mph actual on the prius?

At lower speeds the reports on the c-max are much better, but maybe we need wayne to tell us what hypermiling mpg should be. The ford hybrid looks like it can use pulse/glide + electric milage fairly well. CR reported 35 mpg in the c-max in its city test versus 32 mpg in the prius. That test emphasises cold starts and normal (non-hyper mile) starts and braking.

 

Hummm, " . . . cda is about 30% higher than a prius" gives us something to plug into the aero-drag formula:

Dprius ~= K * cda * (v**2) :: basic Prius aero drag formula minus a whole bunch of good stuff

Dcmax ~= K * (1.3*cda) * (v**2) :: modified CMAX aero drag formula

75 mph :: test point point for Cmax

Taking a back-of-the-envelope:

~36 MPG = 47 MPG / 1.3 :: rough estimate of expected CMAX MPG at 75 mph

~34 MPG measured vs ~36 MPG :: kinda close. <GRINS>

Now we don't have the rolling drag measured for the CMAX to compare to the Prius. This could easily account for some of the difference. It should be somewhat proportional to curb weight, 3,640 lbs Ford CMAX vs 3,042 lbs Prius, plus or minus some technical details on true car geeks care about. The problem is at 75 mph, the rolling drag all but evaporates compared to the aerodynamic drag so we can't use:

1.20 ~= 3,640 / 3,042

We would have to know the Prius MPG at maximum range speed to get a rough handle and my chart hits the instrumentation limit between 25-30 mph. So again, we have to make some simplifying assumptions.

There is ~53% drop in Prius MPG between 25 mph and 75 mph. We will treat this as the aerodynamic drag loss. This give 47% of the MPG as due to the rolling drag at 75 mph. Now we have a scaling factor to apply to the weight derived rolling drag force:

20% greater CMAX/Prius * 47% ~= 10.8% greater CMAX MPG hit on rolling drag

36 MPG / 1.108 ~= 32.49 MPG . . . getting closer but overshot. . . <grumble>

In reality, these are projections against a Prius benchmark based upon rumored values. We really need to find a CMAX owner and a Prius owner and have them each make an MPG vs mph on the same day, same course, and same protocol (no drafting allowed!) Then we'd really know instead of 'stretching the data.'

I would prefer to see the MPG vs mpg data if nothing else to see if there are any 'knees in the curve.' We know the NHW11 and NHW20 had them.

There might be a slight knee at 60-65 mph for the ZVW30. But the temperature changed too much to call 75-80 a definite knee. If we could just get some independent confirmation . . . <gerrrrrr, lazy Prius and CMAX owners!>

Bob Wilson

 

Bob Wilson

 

Classic

 

bob, if you want to graph here are my calculated figures

prius liftback cdA = 5.88
fusion hybrid cdA = 6.81 (16% more than prius)
c-max hybrid cdA = 8.04 (37% more than prius)

For rolling resistance c-max and fusion hybrids are about 18% heavier with a 200 lb load added (driver and stuff). Tires do matter, and it should be much worse with the 18" tire on a ford.

I would expect at lower speeds the ford's to be 18% worse is driver behavior is not taking advantage of the hybrid qualities. At 65+ mph they should get more like their drag loads. In the fusion hybrid we would expect something like 43 mpg if the prius is 50 mpg. In the fusion I could see a driver pulsing up to 60 mph and gliding down to 50 getting similar mileage as the prius if they took the same amount of time to get to the destination.

If the driver is in control, there is the ability to pulse glide at higher speeds in the ford hybrids which may return better than expected results. The strategy to charge the battery during warm up and use it at the end of the trip may also make the ford more efficient if car chooses the correct times.

 

Thanks for the data but there comes a time when we need 'go to the lab and break out the meter.' We can get a vague outline from my MGP vs mph chart but there are so many subtle aspects that could be involved.

We really need to find one of these complaining Ford drivers who lives in an area with a Prius owner and both have some basic curiosity to find out what is going on.

I live in Huntsville AL and I'll check with local contacts to see if we can find a Ford CMAX owner who would like to do some benchmarks. If you' all know of anyone in the North Alabama area who has a Ford CMAX, we can put this to rest pretty quickly. But I'm getting tired of Ford owners coming here to complain about their purchase WITHOUT providing the basic numbers needed to understand their ride.

I'll meet anyone 'half-way' but that doesn't mean 'all the way.' I am not in the market to buy a Ford just for testing. . . . crazy curious, yes, maybe, made out of money, not hardly . . .

<GETTING ON SOAP BOX>

If we could just get rid of egos, an engineer's mileage rally could be fun. But past practices leave a lot to be desired.

<FALLING OFF SOAP BOX>

Bob Wilson

 

I have a Prius v. (Ford desperately wants to compare to a Prius v) I can get to Huntsville.

 

I can tell you, that since Sunday, all my fill ups have been highway miles, majority set at 65 on the cruise. Some at 60, some at 70, and only a short stretch between 70 and 75. there is very little city driving done in either of my cars, mainly rural roads, so for the 2010 it is roughly 70-30 Rural and city, which is why it tends to be on the low side @ 37. Car is rated 36 highway 41 city, and it excels in city traffic, surpassing 41. Most times I drive city I see 45 and up. During the summer it held solid at 40 MPG, only recently since the switch to winter blend and cold temps has it dipped to 37. I expect it, and have no complaints, car is doing great.

However, the new one, has me peeved to no end. I can't get this damned thing to see 40, let alone 47, and 38 is doing good. I just cant seem to get this car to hit anything over 40 MPG on the instant MPG gauge, unless A, I am braking, or B, on EV and slowing down. Pulse and glide seems to make it worse. It takes quite some pedal to move it, and have to get it over 2000(just guessing thats what the second bar is), to start going faster. In the 10, maintaining the speed limit, whether its 55 or 65, I can pretty much get the instant to readout out at or above 40 MPG, but this new one, somewhere in the low 30's unless going downhill.

I dont know what else to do with it at this point, have to wait until I get home and have the dealer look at it. Temps have been in the 70's, which should have made it even easier to get in the 40's. Since it has a 13 gallon tank, it only has a 400 mile range, which is another thing ticking me off.

 

If there is someone near Lakeland FL who would like to try my Fusion, I would love to see them try to get 47 out of it, and if they can, show me what the hell I am doing wrong, cause I sure cant figure it out. How the heck I can average 53 MPG over 23K miles, and have a high tank of 75 in a Prius, and cant even get 40 MPG out of this Fusion, when I can do it easily in my 2010, is beyond me!

I am here until Friday morning when I leave for home.

 

You answered you own question. Ford Fusion is not a Prius.

 

No it isnt, and my 2010 Fusion hybrid to me is a better car than the Prius was that I had. I also have no complaints with my 2010, which is why I still have the 2010. I have many complaints with my 2013, the biggest being it is NOT getting anywhere near EPA.

I have taken into consideration all the factors, new car, break in period, weather, etc. OK, 2100 miles, past break in, check, Tires at 45 PSI, check, Temps in the 70's, no AC needed, Check, still returning 36 MPG, PROBLEM!

 

So the new 2013 Fusion is getting less MPG than the old 2010?

 

Can you measure MPG at cruise control set speeds for 10 level, dry miles at:

• 30 mph (~20 min)
• 40 mph (~15 min)
• 50 mph (~12 min)
• 60 mph (~10 min)
• 70 mph (~9 min)

Your time may be short but if you can get the end points and one middle, it would help.

Is it a rental or one you are driving home?

My first set of data came from two hour segments on an 800 mile trip back to Huntsville on I-20. Just set the cruise control at some fixed speed and run long enough that the trip meter MPG does not change. Record the speed before exiting cruise control and note any effects that might impact the mileage such as head wind, starting and ending altitude changes, e.t.c.

Remember Issac Newton worked out the laws of motion when the most common 'watch' was ones own pulse. We should never let 'perfect' be the enemy of 'good enough.' The gold standard is whether or not the results are repeatable. So don't let my emphasis on better abort getting 'good enough.'

Bob Wilson