Hypermiling the C-Max

[C-MaxJaxon]

Someone has probably posted a link to this before, but here's a new thread so it's more visible to new people. This is an ongoing discussion of some C-Max hypermilers.

 

http://www.cleanmpg.com/forums/showthread.php?t=46128

[C-MaxJaxon]

Here's a chart from Wayne on the same forum in another thread that compares the C-Max and Prii mileage at multiple highway speeds. My guess for the C-Max would have been from high 40s dropping down to low 40s.

 

http://www.cleanmpg.com/forums/showpost.php?p=368315&postcount=273

 

[CNCGeek]

Interesting graph and the forum there is full of great info.  Reading some of the posts there it looks like it was compiled from tests run at different speeds (steady state) and he attempted to keep the battery around 50% at the end (so I'm guessing he started at that as well).  It was indicated in some posts that the testing was done as a 10mile drive for each speed with a +/- 10 ft difference in elevation from start to finish.  Seems like a really decent test, but also surprising - makes me hopeful for an improvement in my fuel economy.

[darrelld]

Those chart numbers look very close to what I have observed. I have extended that test up to 75 mph where it drops to 32 mpg with 40-45 degree ambient temps

Edited January 20, 2013 by darrelld

[ptjones]

I would have thought you would see big jump up at 62mph being able to go into EV good percentage of the time. I know I can stay in EV at 63mph and at least get 50mpg with covers at 70deg.F.  I also think CMAX would catch up with PriusV by 50mph. 

[darrelld]

<blockquote class='ipsBlockquote'data-author="ptjones" data-cid="6811" data-time="1358710167"><p>

I would have thought you would see big jump up at 62mph being able to go into EV good percentage of the time. I know I can stay in EV at 63mph and at least get 50mpg with covers at 70deg.F. I also think CMAX would catch up with PriusV by 50mph.</p></blockquote>

 

Those curves are converging fast, would be interesting to see an honest Prius mpg report @ 75 mph.

[ptjones]

<blockquote class='ipsBlockquote'data-author="ptjones" data-cid="6811" data-time="1358710167"><p>

I would have thought you would see big jump up at 62mph being able to go into EV good percentage of the time. I know I can stay in EV at 63mph and at least get 50mpg with covers at 70deg.F. I also think CMAX would catch up with PriusV by 50mph.</p></blockquote>

 

Those curves are converging fast, would be interesting to see an honest Prius mpg report @ 75 mph.

I agree with you. My mileage keeps getting better.

[Tdefny]

Interesting graph, especially that the Prii did so much better than EPA while the Max met EPA on this test at 60 (but fell off at higher speeds).

 

 

Everyone keeps talking about the C-max EV capability up to 63. This may be inportant, but the traction motor still should make a useful contribution above this speed even though the ICE must run. One of the thing that Toyota has mastered in the Prius is the blend of power between ICE and traction motor. The max "EV" speed on my early generation Prius is 42, but mileage doesn't drop noticeably until above 62.

 

 

There may be mechanical differences in the powersplit approach between Ford and Toyota that hinder that blending. I would have thought that the Max should blend power better with a larger motor and battery, but it seems to prefer maximum time in EV mode, rather than blending. This seems logical, but maybe isn't the best they can do. More likely, it is just a heavier car with more wind resistance and a bigger ICE and this is the best result they can get under these conditions. I do believe that Ford would have looked at all sides of the equation and come up with the best solution they could with this design.

 

 

One thing is for sure. Our mileage should improve as our cars get broken in, the weather warms, and we learn the best ways to drive them. These same conversations took place with the early Prius and people had all sorts of theories of the best ways to stretch the fuel, often based on how to drive the Insight, which was a very different car. Eventually things improved and other topics dominated the forums. For me, dumping pulse and glide and driving as if I had a balloon between my foot and the pedals immediately and consistantly gave the best mileage.

Edited January 22, 2013 by Tdefny

[roninsd]

The Engage mode does show the electric supporting the ICE when running at higher speeds.  I had thought is was one or the other, but found that they do in fact work together to support the better mpg at higher speeds.  When running at 65 mph, I am currently maintaining 40+ mpg overall.

[Tdefny]

It is a lot harder to see in the Energi because the limit is higher. I plan to explore this a bit further on my next highway trip.

[Jus-A-CMax]

The Engage mode does show the electric supporting the ICE when running at higher speeds.  I had thought is was one or the other, but found that they do in fact work together to support the better mpg at higher speeds.  When running at 65 mph, I am currently maintaining 40+ mpg overall.

 

Ron - next time, take note of the battery level when that happens. My suspicion is that an-almost-fully charge battery level improves the ICE MPG performance even at higher speeds. Anything less than 80%, say 1/2, does not effect it as much. 

[altabrig]

I would have thought you would see big jump up at 62mph being able to go into EV good percentage of the time. I know I can stay in EV at 63mph and at least get 50mpg with covers at 70deg.F.  I also think CMAX would catch up with PriusV by 50mph. 

 

Wife and I drove ours today and were getting around 45mpg at 65.  Time will tell.  Hopefully posters hear will dial in this little max's sweet spot,  My 06 prius was usually 41.  If I was heavy footed it was 38,  Best tank was 56 - limited by several days with 40mph limits in YNP and then a cruise back to ID.  75mph =40mpg max in a Gen II prius for me. 

 

Good to be back in a Ford,  sold my 92' twin tanked F-150 5.0L due to gas prices in 06 going to $3.25 and getting sick of filling the two 20 gallon tanks.  Hope this little sucker works out.  Seems to be a tight engineered lil' eurominvan with very high qc.

Edited February 4, 2013 by altabrig

[rkk]

Being able to go up to 62 mph in EV mode is just a gimmic if you are driving any distance on the freeway (but probably very helpful on the EPA test). Where does that battery power come from? The gas engine.The result when using ev mode once the battery has to be recharged so much power is pulled off the engine to recharge the battery that the mileage drops significantly until it is charged up again. The best highway mileage I have seen by far is at 65 mph with a nearly full battery indicator. No need for regen so the ICE can just power the wheels. The best thing Ford could do is to give us the EV now or later button similar to the energi. It could be a software button. If they can't do that they should rebalance how much engine power is pulled off for regen at higher speeds.

Edited February 19, 2013 by rkk

[HannahWCU]

I noticed an interesting mode this morning with my CMax. I am using a scangauge and I set the (eco) cruise to 65-67mph most mornings for my 22 mile highway run to work (speed limit is 65). This morning I was lucky enough to get behind a bus doing the same speed. On a couple of downhill sections of road, my scangauge was reading 9999mpg (indicating EOC), rpm was reading ~900, engauge screen was indicating no power from ICE (no white bar visible) but the blue bar was about halfway, indicating the EV motor was powering car. anyone else seen this. I saw it go into this mode twice. (and yes I was traveling above 65 MPH, and the display was NOT displaying EV)

Edited February 19, 2013 by HannahWCU

[plus 3 golfer]

Yes, I've this many times when recording real time data via OBDII port with cruise at around 65 mph.  WIth cruise set  at 70 mph, I've not seen it although maybe it's because of gearing or maybe just need a steeper hill.  

[rmcmast]

Ron - next time, take note of the battery level when that happens. My suspicion is that an-almost-fully charge battery level improves the ICE MPG performance even at higher speeds. Anything less than 80%, say 1/2, does not effect it as much. 

 

This is consistent with what I see. When the battery is less than 60% or so any pressure on the pedal takes you down to 20mpg or lower. In Eco Cruise I've seen the mpg rise with the ICE on as the battery charge rises.