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Two things. Data on battery life indicates that Li-ion have superior longevity to NiMH. The dotted curves are Ford's Key Life Test results, showing far slower degradation with Li-ion. The dots are actual data for NiMH batteries showing the Key Life Test is conservative. C-Max uses Li-ion, Prii NiMH. http://www.designnews.com/author.asp?section_id=1366&doc_id=256425&dfpPParams=ind_184,industry_auto,bid_318,aid_256425&dfpLayout=blog Don't discount regen braking. Most of us are on our brakes pulling into the driveway, resulting in a bit of a boost for the battery. Some of even live at the bottom of a hill! HAve fun, Frank

Not if you have the kick-to-open tailgate!

Planning to visit our son in Baton Rouge in February; I'll let you know our plans after the holidays. Have fun, Frank

Congratulations, and a lesson for us all on what to do when the update fails! HAve fun, Frank

FWIW, ours was valued as part of my father-in-law's estate. 10 months and 8K miles after purchase, the book value on an SEL with 302A and pano roof was $25,000. I suspect dealer trade-in value would be significantly less. Have fun, Frank

Same question in my mind, but right along side "Have you done the PCM update yet?" Recall 13B07? Pre-update, ICE is on above 63, and I can't see a) keeping it below 63 on the way down and b) want to when you have a 180 minute commute. HAv efun, Frank

http://fordcmaxhybridforum.com/topic/2875-tool-for-the-third-dimension-mapping-route-altitude/ Try this... and let us know how you do! HAve fun, Frank

Is that the the fall line of the Piedmont? we're seeing in your route? HAve fun, Frank

This is my way to work. My high point is a gentle bend in the road with a very slight rise. Needs some ICE every time. Very subtle, but then, the whole route only moves ~100 ft. peak-peak... and I can feel each of the gentle hills in how long EV lasts. That little blip in thie middle has an S-turn at the bottom that's reminded me how to take a turn! Have fun, Frank

I'm doing something similar (recording consistent round trips) using a ~15 mile route, and will post results when I have enough data to say anything. The first thing I see is a temperature effect. Try adding the outside temp and perhaps a special weather note as I expect both of these to add variability to the data, no matter how consistent your driving style. You may also want to group in round trips, as that takes net elevation change out of the picture. Mine are in pairs. Have fun, Frank

Actually, its not the web site, it's the units. You need to know if it's mass (megajoules/kilogram) or volume (megajoules/liter) being compared. Diesel fuel has greater mass density than gasoline, it's a lower fraction (larger molecule) in a refinery stack. You get more heat per gallon because there's more fuel there. Wiki puts it well. "As of 2010, the density of petroleum diesel is about 0.832 kg/l (6.943 lb/US gal), about 12% more than ethanol-free petrol (gasoline), which has a density of about 0.745 kg/l (6.217 lb/US gal). About 86.1% of the fuel mass is carbon, and when burned, it offers a net heating value of 43.1 MJ/kg as opposed to 43.2 MJ/kg for gasoline. However, due to the higher density, diesel offers a higher volumetric energy density at 35.86 MJ/L (128,700 BTU/US gal) vs. 32.18 MJ/L (115,500 BTU/US gal) for gasoline, some 11% higher, which should be considered when comparing the fuel efficiency by volume." While we normally do Chemistry in terms of mass of components, we sell fuel by the gallon... HAve fun, Frank

Glad to hear of more ways to the data, and I was going to say something about great mileage on the downhill side before I appreciated you do this on 2 wheels and >1HP... more power to you! HAve fun, Frank

I wondered, too... per 3rd printing of the manual: "Help Press the Settings icon > Help, then select from the following:" And "Where am I" is in the list that follows, if you have MFT. I've got to look tonight. HAve fun, Frank

One reason diesels are efficient is their lack of noxious emissions at lean burn conditions. They have no "air-fuel mixture." so fuel consumption is not tied directly to RPM as with emission-controlled gas. When you direct-inject only the fuel you need to maintain desire RPM at some load, there's less waste than pumping a constant air/fuel ratio at every RPM with no regard for load, energy required. You also see economies of scale; the lowest consumption engines are megawatt generators. I assume no one here misses the irony that the VW TDi Sportwagon actually delivers 47 mpg... my Brother-in-law has one, and gets 38MPG in the C-Max driving it like his VW... on Interstates, of course. HAve fun, Frank

I haven't driven a Prius, but i would welcome a reduction in throttle sensitivity at the very low end. Yes, when you put your foot into it, it should scoot. At the same time, I'd like to stay in EV mode occassionally without watching the display! Have fun, Frank PS interesting article. I'll take exception to some of this comments (1.8L with 11:1 compression, 141hp and 129 torque would not be unusual today), but he did give me one insight. Atkinson cycle engines don't rev well. They work best in CVT-type applications, and need EV for throttle response. Balanced compression engines have more pressure in the cylinder when the exhaust valve opens. Unbalanced compression/power stroke engines will have less pressure in the cylinder due to the added expansion. As you remove intake vacuum (open the throttle), the engine gets less kick starting an exhaust/intake stroke due to the added expansion. That's where the efficiency comes from! No freee lunches...

Trying to be funny... our answers improve your mileage, but we're just full of hot air, at least in my case. I never claimed to be a comedian! Frank

Bear, I don't know your background, you've missed the key bit about horsepower: it's irrelevant. Another marketing scam to get you to buy something you don't want and can't use; a car salesman's dream! ICEs produce torque, and torque x RPM = HP. Lengthening the power stroke increases torque. Getting a 2L power stroke for every 1.8L of intake displacement improves efficiency as well. Both show an advantage for Atkinson. So how does more torque result in "less power?" It doesn't. Running at lower RPM results in less power, while capturing huge efficiency advantages. Look at a BSFC (brake specific fuel consumption) chart and you'll see that high RPM requires high fuel consumption. Kind of makes it seem like horsepower is a bad thing... which it's not, its just an unimportant thing to an automotive engineer. Now the added weight of an Atkinson makes a difference... Have fun, Frnak

How'd you get yours to run on hot air?

Hannah, as long as you got there, I'm happy! obob, I didn't give directions because I'm no more qualified that you to do so. We're all learning by doing, like HannahWCU salsa, I expect this to be ubiquitous in the app world; smart phones are the right device (size, weight) for cycling apps. Altitude is far more important in an organic hybrid; cars communicate but muscles get your attention. Dave, given you see a similar level difference to Hannah, do you also see a similar difference in MPG? Jus, I'll be very interested in what you find, given your results... is there logical explanation for you and Recumpence (or are you Aliens)? Have fun, Frank

Glad you figured it out; any idea what's different? I haven't seen associated kml files, and I'll update the first post if there are other ways to get there. 300' is ~100m elevation change, equivalent to about 1.7MJ or about 6-8 oz. of gas (@ 20-25% ICE efficiency)... the difference in fuel consumed over 25 miles between 47 and 53 MPG is about 0.05 gal, or 6.4 oz. It would appear you're doing a great job of managing the powertrain through the hills, as the difference in fuel consumption is of similar magnitude to the energy gained going down the hill in the first place. HAve fun, Frank

It's innacurate to say that an Atkinson cycle engine sacrifices power for fuel economy. The engineers traded off weight for efficiency, not unlike gas vs. diesel. A 2.0L engine weighs more than a 1.8L engine. Letting 1.8L of fuel/air mixture do additional work expanding to 2.0L captures more energy from that 1.8L of air/fuel. Ford could as easily have upped the power by increasing the operating RPM (remember, horsepower is torque x RPM), with an associated fuel economy penalty. RPM's the only reason diesels "sacrifice power;" they have plenty of torque, just like the C-Max. HAve fun, Frank

I find MTE a bit capricious as it seems to have a very short memory. One might think it would use the lifetime average MPG, but it seems to be adaptive, showing greater range when the car's being driven more efficiently. As long as you drive consistently, and don't decide to hot-rod it home, you should be fine. If you just came down from the mountains, fill up right away!!! HAve fun, Frnak

At the system level, yes, but looking only at the ICE alone, the situation is reversed; you get more energy per gram of gasoline going uphill than you do going down. The reason is engine load. I haven't seen a Ford-specific BSFC chart, so I'm pulling this from Tim Gulden's analysis. The contours are equal fuel usage per kilowatt hour supplied. The optimal operating point for this engine is where fuel usage is minimized at 220g/kWh. Move outside the "puddle" at the minima and energy costs increase in the form of greater fuel consumption per kWh. The trick, of course, is that you don't create of destroy energy, just move it from one form to another, with finite losses at every step. The gas burned going uphill gets stored as potential energy for use coming back down. However, you'd need more gas to generate the same amount of energy while you're coming down because you'd be running the ICE at higher BSFC (away from the optimal "puddle") due to insufficient load. Energy balance is the first step to understanding how to operate a hybrid - knowing how to move energy around among kinetic, potential and electrical storage options, and when to use ICE. The next step is optimizing energy transfers, like learning 100% re-gen braking, and how to load the ICE to minimize BSFC. It's what Jus's MPG tips are all about. When climbing hills: "...I stick to the right lane, power bar up to the second level where the battery charges and climb..." Have fun, Frank

I hadn't seen anything much on route altitude here, so let me point you all to a little tool called GPSvis. I found it looking for a way to assess altitude changes on various commuting routes. Turns out the bicyle community has this sussed. Start by plotting your route on Google Maps Above the start/end entry area you'll see a link icon. Click and copy the resulting URL Open GPSvis to the input page linked above. In the lower right, above "Draw the Profile" is a a box labeled "Provide the URL of data on the web" Enter the Google link into GPSvis URL input box and "Draw the Profile". You get this: This is for my expressway commuter route. The dip is a bridge over a canyon-style bay. As to "what does this all mean?" On another thread, I developed this chart showing the relative energy content in an operating hybrid. (link to that thread) In my commute path shown above, I drop about 30 feet from home to office parking lot. That's about 10m, which I've estimated at 0.16MJ under "Potential Energy" in the diagram. I also realized tonight that 1MJ (megajoule) is the energy contained in 0.99 ounces of gasoline. My ~10m altitude change is "worth" 1/6 oz. of fuel. Going to Mammoth may be worth more... What can you do with altitude data? Pick a route with fewer steep hills, perhaps? Nahhh.... I think the value is in understanding your route, where your low and high spots are, so you know when it's OK to be on the ICE longer and harder. My rural commuter route's high spot is a gentle crest on a fairly flat road, not the steepest hill. The lowest spot is a dip over a culvert on a state highway, not the 1-lane railroad underpass around the corner. Someone like Jus may find some of his routes have a pattern that fits well with the C-Max's energy storage/discharge capabilities. After some more baselining, I may try different altitude-profile routes to see if more up/down makes a difference (betting it does; re-gen's only like 90% efficient if you score 100?). HAve fun with the toy, Frank PS I should have noted that it's inaccurate to treat energy in gas as if it were as accessible as energy in the battery, or due to hilltop location. ICE efficiency is in the 60-70% range, with only about 20% reaching the road (where it's dissipated by rolling resistance and drag). My -10m altitude change is worth more like 1 oz. of gas in terms of energy to the road, not 1/6 oz.

Well, I live on a slight hill... the hockey stick is my street. Turns out it's almost a 30' drop (10m = 32.5')' so I tried the free roll test. Stopped near the top of the hill, put the transmission in N and let it roll down to the cul de sac. Just hit 25 mph. The Potential Energy numbers appear to be in the ballpark. Frank