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Actually this isn't OVMS, it's a little £6 OBDII Bluetooth dongle and the free MyGreenVolt app (search elsewhere on the forums for details). I do use Hold whenever I'm on longer trips as it saves sitting at the traffic lights sometimes with the engine revving at 2000rpm while it tops up / replenishes the buffer, which gives you strange looks from nearby people in cabrios!
 

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Ah yes, sorry that's what I meant. I've also got the cheap OBD2 dongle but the app isn't available for my Samsung phone and the level of android it's on! Very frustrating. :mad:
 

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How annoying :( You might be able to find the .APK installation file elsewhere (or contact the authors for it) then install it manually...
 

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How annoying :( You might be able to find the .APK installation file elsewhere (or contact the authors for it) then install it manually...
Nah, buy a new phone that's much more fun. I've reserved a Motorola Moto G for pickup from Argos soon. It should work on that. :D
 

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This is why the engine normally hums away at about 2200rpm when it's doing its buffer charging, as this is the most economical/efficient RPM for the Atkinson Cycle that the engine is running.
Exclusive: Chevy Volt Generator Does Not Use the Atkinson Cycle - GM-VOLT : Chevy Volt Electric Car Site GM-VOLT : Chevy Volt Electric Car Site

Not trying to be picky with other peoples posts but I had to Google the Atkinson cycle engine on the Volt/Ampera as I always understood it was an almost standard Corsa lump.
I think the GM engineers did a fine job on the electric drive but reached into the parts bin for the engine.
Maybe on Volt 2?
 

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Yeah, I think you might be right actually Russ, I was getting my wires crossed with the Prius' engine. @donald will know, he knows everything :)
 

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That article is a bit of baloney about the strokes per cycle. An Atkinson cycle is an over-expansion cycle, in which the crank is offset to the rods allowing the expansion stroke to be longer than the intake stroke. This means that the exhaust is expelled cooler than in a 'symmetrical' conventional Otto cycle because more of the gas energy is extracted through the greater expansion and longer stroke.

However, for the Ampera's LUU engine, it does what GM describe as 'Atkinson-like' by having a shorter intake valve phase and longer exhaust phase. This achieves a similar effect, but not quite the full efficiency levels of a dedicated geometry.

The reason Atkinson cycles are not routinely used in cars is because they don't do transient conditions very well, they like to run constant and steady. Ideal for serial EVs but not so great under transient load conditions. With variable valve intake you can switch from 'Atkinson-like' to 'normal Otto' in one revolution, so you get some of the benefits of an over-expansion engine with all of the benefits of an Otto cycle.
 

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See, told you Donald would know :) Thanks!
 

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I can attest that @donald isn't James May, having met him (Donald that is, not James ;)) - and I suspect he knows a lot more than even James May would! :) I know that he works in the auto industry for a supplier of car manufacturers' black box electronics systems, so he would know a lot, but even so... some inside knowledge there somewhere, methinks... :censored:
 

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Guys! Slightly embarrassed by the kudos! I'm just an average engineering nerd, I guess. Just 30 years of reading lots, most of it remembered and some forgotten (fortunately, more remembered than forgotten!). Plus a couple of decades in various developmental roles in automotive and aerospace related stuff. A few patents in vehicle steering, RF signalling, high voltage electronics, particle accelerators.... the usual stuff people patent in their spare time ....

I can look at a machine or a diagram of a machine and instantly understand it and start thinking about how it works, implications for its construction, materials needed to make it, how it relates to other technologies, solutions to issues I can see with it already, etc..

It seems to me that I look at machines and understand them in the same way that some folks can look at and listen to people and understand them. For me, I look at people (especially women) and haven't got the slightest clue how they work or where to power them down or reprogramme them, while for others they appear to think the same about technology!

I presume you've all seen;-

 

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Hello All

Now i am new to this, so i am not sure of the rules but i took this picture the other day. I was using mountain mode a lot especially going uphill and it was a long trip.I was very surprised to see this.

Any comments?

IMG_2470[1].JPG
 

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@Malcolm Dykes
The 18.2kW used says it all with a 10.4 kW max battery.
Most likely burning dinosaurs uphill has allowed regen downhill to boost your range. I often get 1 mile back on a long downward hill.
The only true way to achieve max range is no fuel use at all. Not Hold or Mountain mode.

Sorry old bean.
 

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72.6mi/18.2kWh = 4mi/kWh.

Sounds reasonable.

That would mean a range of around 42 miles on one charge (10.5kWh).

The extra 7.7kWh has been generated from burning petrol.

Overall the 2.12 gal would have generated around 28kWh, so added to one charge's worth or 10.5kWh, you have covered 187.7mi/38.5kWh[equivalent] = 4.9mi/kWh which is very good for a mixed run.
 

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Yep, that is good. I've always said Mountain Mode is best for long journeys, if you engage it just before 50% battery left, but I keep getting shot down :rolleyes:
 

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I think I understand what you are all saying. So does it qualify as a +70 range on one charge or can't we use petrol at all?? Confused.
 

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Try as I may I'm averaging approx 45 miles from the 10.5 KWh PP3's and 55 mpg on the Ecotricity avoiding juice.
My journey summary shows additional charge milage as petrol miles, not battery miles.?

(edit )I forgot , the regen actually deducts KWh off the charge used , it's all V confusing !
 

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I think I understand what you are all saying. So does it qualify as a +70 range on one charge or can't we use petrol at all?? Confused.
The 'rule' such as it is has been repeated on each of these mileage threads, the original idea was to see how far people could get on one continuous run in normal mode only from full battery to the time it switches to petrol.
 
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