Why wouldn't Ford have EPA test the new 2014 C Max. ?

[catsailor]

I know that the 2013 was re-tested with the FE mods but given the history of this car and the claimed mods Ford has done I think this is a good PR move on Ford's end to do another final test to verify once and for all what they can advertise this car at. I don't think they will ever get to 47/47/47 although guys like Jus and Matt would disagree :)

 

I think improving highway FE maybe hard give the lack of an aerodynamic shape of the car but in the end I think final testing will put the consumer at peace with the FE numbers...2013 numbers which you bet EPA triple checked were 40 hwy and 45 city for 43 MPG combined...... I doubt they will do much better but I would like to see me proved wrong...NO WAY 47 combined because that is way too large a leap forward.

Edited January 4, 2014 by catsailor

[plus 3 golfer]

Ford needs to shave about 4-6 hundred pounds from the C-Max (not an easy task from a 3607 pound car) and with the aero enhancements the rating could get to 47 mpg overall.  Also, you might want to edit the "42 hwy" number to "40" mpg as 40 is the revised EPA number. 

 

The 2014 EPA numbers for the C-Max Hybrid haven't been released yet likely because Ford is testing the "enhanced" 2014 C-Max and will certify the results to the EPA for the Monroney sticker.  

[catsailor]

thanks on the revision catch and you are correct a heavy car for sure. I think this is also why it felt good on wet roads and some ice.

[catsailor]

 

 

The 2014 EPA numbers for the C-Max Hybrid haven't been released yet likely because Ford is testing the "enhanced" 2014 C-Max and will certify the results to the EPA for the Monroney sticker.  

 

 

the EPA Dyno test wont find the aero changes at all, those need to be shown on the road under actual driving. The trans changes it may find in acceleration and gearing.

[Jus-A-CMax]

nvm.

Edited January 4, 2014 by Jus-A-CMax

[ptjones]

the EPA Dyno test wont find the aero changes at all, those need to be shown on the road under actual driving. The trans changes it may find in acceleration and gearing.

I thought I read somewhere that the new transmission was from the Energi? :)

 

Paul

[plus 3 golfer]

 

I thought I read somewhere that the new transmission was from the Energi? :)

 

Paul

I interpret the quote below from Ford that the 2014 C-Max Hybrid will have an effective taller final drive ratio than the 2013 Hybrid (hardware changes for more efficient drive ratio).  I don't believe that the shorter final drive ratio of the Energi will be more efficient in the Hybrid.  IMO, the C-Max FE suffers at higher speeds (higher ICE rpm that may not be the most efficient point on the BSFC) and will benefit from a taller final drive.  But time will tell. 

 

 

The 2014 C-MAX also will benefit from several hardware changes, including:

• Gearing changes that result in a more efficient transmission drive ratio
• New hood seal, front and rear tire deflectors, A-pillar moldings and the addition of rear lift gate deflectors to improve vehicle aerodynamics
• New engine oil with reduced friction

 

 

 

the EPA Dyno test wont find the aero changes at all, those need to be shown on the road under actual driving. The trans changes it may find in acceleration and gearing.

The dyno factors in "road drag" including aerodynamics.  A number of years ago EPA allowed wind tunnel data to be use in computing the "road drag" to be used in the dyno tests.  Prior to that, coast down data was used to determine road drag.   Both procedures may still be allowed but would have to research.

 

Also, in the retest of the C-Max Hybrid, the reason given as to why the Fusion Hybrid was not a good proxy for the C-Max in the EPA tests was aerodynamic drag difference between the Fusion and C-Max.   Prior to the reprogramming of the Hybrid the EPA test numbers were 40 highway, 42 city, 41 combined.  The difference is 6 mpg combined from the 47 mpg rating which was primarily attributed to drag.  The Cd of the Fusion is 0.27 and may have a smaller frontal area than the C-Max.  The Cd of the Hybrid is 0.3.

[ptjones]

I looked up spec. for CMAX and FFH height 63.9"/58.2" and width 72"/72.9" and lenght173.6"/191.8".  FFH weighs 15lbs more. So CMAX is 5.7" taller and pushing more air. :) 

 

Paul

[plus 3 golfer]

Using those dimensions, I get that the CdA of the C-Max is 20% less aerodynamically efficient than the Fusion. The 20% is not the FE difference.  The effect of the 20% varies with speed.  At lower speeds below 40 mph, the effect will likely be less than a 10% change in power requirements.  At 70 mph the effect will likely be around 14% change in power requirements.  The change in FE depends on where ICE is running on the BSFC.  Given that the PCM can change where ICE runs by operating MG1 and MG2, the effects of the increased power requirements on the C-Max FE can be minimized.   This raises questions on Ford's EPA 47 mpg rating of the Fusion as a 6 mpg overall difference between the Fusion EPA rating and the EPA re-tested C-Max Hybrid rating of 41 mpg seems more than one might expect for the aero differences (6/41 = 14.6%).

 

As a reference, here's a table showing aero data for various vehicles.  Note the Prius 2010+ has a CdA of 5.84 compared to my calculations of the CdA of the C-Max and Fusion of about 8.05 and 6.68, respectively (using the frontal area calculation in the table).  IIRC, the Prius V has a Cd of 0.28 and a larger frontal area than the Prius hatchback.  So, I would expect the CdA of the Prius V to be around 7.0+. 

Edited January 5, 2014 by Plus 3 Golfer

[ptjones]

Driven both cars I don't think there is more than 2mpg actual difference in FE and probably less on the HYW.  In City driving the CMAX may get better MPG's. IMO :)

 

Paul

[plus 3 golfer]

Driven both cars I don't think there is more than 2mpg actual difference in FE and probably less on the HYW.  In City driving the CMAX may get better MPG's. IMO :)

 

Paul

In various reviewers tests, reviewers seem to get about a 2 mpg difference. Of course generally the reviewers aren't comparing the two cars at the same time and likely not under the same driving conditions.  (I'm editing my post above)

 

I didn't want to bring this up in my post above but I question Ford's original rating of 47/47/47 for the Fusion Hybrid.  The Fusion Hybrid is almost in Prius hatchback EPA FE range.  It makes no sense that the EPA FE of a 600 pound heavier car with a higher Cd and larger frontal area could be that high without a few more "loopholes" in the testing procedures. IMO, the EPA retest of the C-Max Hybrid has to raise concerns about the Fusion Hybrid FE rating and rating of Hybrids in general.  As has been discussed before, EPA is supposedly looking at the Rules for Hybrids, going to close loopholes, and hopefully make changes to better reflect the real world.

[fbov]

I'm surprised no one's gone back to the EPA test summary as I see an obvious reason the FFH wins - gearing.

 

Per the EPA, the sedans (FFH, MKZH) have 3.61 axel ratio, the C-Max (both Hybrid and Energy) have 4.09 ratios. FFH also has 250 lb. lower test weight, so it shoud be the winner... and it is!

 

Here's the EPA data...

 

(this is where the data would be if it survived posting. gibberish deleted)

 

You'll have to look at the link yourself. Filter the 2013 file for manufacturer FOMOCO and tranny type CVT to find the 8 records of interest (2 ea. Hybrid, Energi, FFH, MKZH).

 

HAve fun,

Frnak

Edited January 7, 2014 by fbov

[plus 3 golfer]

I'm surprised no one's gone back to the EPA test summary as I see an obvious reason the FFH wins - gearing.

 

Per the EPA, the sedans (FFH, MKZH) have 3.61 axel ratio, the C-Max (both Hybrid and Energy) have 4.09 ratios. FFH also has 250 lb. lower test weight, so it shoud be the winner... and it is!

 

Here's the EPA data...

 

(this is where the data would be if it survived posting. gibberish deleted)

 

You'll have to look at the link yourself. Filter the 2013 file for manufacturer FOMOCO and tranny type CVT to find the 8 records of interest (2 ea. Hybrid, Energi, FFH, MKZH).

 

HAve fun,

Frnak

 

Please look at the data again. :)   I have looked at the data many times.

 

The 2013 EPA data shows the Ford C-Max PHEV (Energi) with the 4:09 (there are 4 line items) and the Ford Fusion Hybrid HEV (2 line items) with the 3:61.  Ford did not test the C-Max Hybrid but used the Fusion Hybrid data for the C-Max Hybrid nor did they test the Fusion Energi.  The 250 pound weight difference is the difference between the Fusion Hybrid and the C-Max Energi which has the larger Battery Pack. 

[ptjones]

Per the EPA, the sedans (FFH, MKZH) have 3.61 axel ratio, the C-Max (both Hybrid and Energy) have 4.09 ratios. FFH also has 250 lb. lower test weight, so it shoud be the winner... and it is!

 

I'm confussed, I looked it up and the CMAX is 15 lbs lighter than FFH. ;)

 

Paul

[fbov]

Plus3,

Given that the 4 C-Maxs have the same vehicle ID, there is no other conclusion to be made; I misinterpreted the data. The weight difference is due to the plug-in's battery as you say.

 

But it's the axel gearing difference that's significant to fuel consumption... and negates any possibility of rating the FFH and CMax mileage equally without smaller tires on the FFH.

 

... and then I look at the FFH spec sheet... 2.57 and 2.91:1 for Hybrid and Energi respectively so I may be all wet here, too. No data from Ford on axel gearing, but the top speed (115 Hybrid vs 102 Energi) would imply higher numerical gearing in the the Cmax Energi, as it is in the Fusion.

 

In my best Emily Littella... Nevermind.

 

My apologies, Paul, if I led you down the same rabbit hole.

Edited January 7, 2014 by fbov

[plus 3 golfer]

If one goes to etis and enters the VIN, it shows the axle ratio of 2.57:1 for the 2013 C-Max Hybrid the same as the FFH.  If someone with an C-Max Energi, FFH, and Fusion Energi could do the same and post, we can validate the axle ratios.  I believe we will find both hybrids are the same and both Energis are the same as reviewers have been stating for some time. 

 

When I had my one month membership to the service manuals one could print off a detailed spec sheet and detailed build information for any VIN.  My printout shows 2.57:1.  Also, here's a snip of my etis below showing the 2.57  

 

[ptjones]

I just got the Helm Ford Service information CD today, YA!  So hopefully I will be able to come up with answers on the CMAX Hybrid/Energi.  The first chance I get I will look at it. :yahoo:

 

Paul