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Howdy everyone!

I'm trying to get all the vehicle advanced settings filled in for my stock 2011 pure into the Dashcommand software. I search around seeing if someone had already post something to fill in the the blanks. Does anyone happen to has the info it's requesting available?

-Castmem
 

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Did you ever get some answers? I just bought a ODBLink MX (WiFi) and Dashcommand and gathering the same data.

Here is the data I have so far (some a rough guess) for 2008 451 Passion

Fuel tank capacity - 8.7 US gallons
BSFC - .45 (?) lb/(hp/h)
Volumetric Efficiency - 85%
Drive ratios: Axle 4.529; 1st 13.912; 2nd 8.664; 3rd 5.697; 4th 4.271; 5th 3.456
Curb weight 1808 lbs
Drag coefficient - 0.35
Frontal area 2.06 m2
Max engine speed 6400 rpm
Min engine speed 942 rpm (?)
Shift point 2000 rpm
 

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I am changing a few settings:
Drive ratios: Axle 4.529; 1st 3.308; 2nd 1.913; 3rd 1.258; 4th 0.943; 5th 0.707
(The earlier settings were approximate final ratios not gear ratios)
Min engine speed 1500 rpm (in gear)
 

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Thanks so much for these useful values! I have no idea where you got them from, I've been searching endlessly over the Internet but couldn't find them all...

One question remains, though: when specifying the wheels/tires, should I use the setting for the rear ones or the front ones? I'm using the rear ones because they're supposed to be the ones with power; but I understand that things like speed are calculated based on the wheel radius, and I noticed that the speedometer is a bit off on the DashCommand app — it shows a slower speed than the Smart's speedometer. This may be deliberate — forcing people to actually drive a bit slower for safety reasons — or a question of twiddling with the settings (there is an option for that, but I have no idea what to put there — is it a ratio, a percentage, what...?).
 

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One question remains, though: when specifying the wheels/tires, should I use the setting for the rear ones or the front ones? I'm using the rear ones because they're supposed to be the ones with power; but I understand that things like speed are calculated based on the wheel radius, and I noticed that the speedometer is a bit off on the DashCommand app — it shows a slower speed than the Smart's speedometer. This may be deliberate — forcing people to actually drive a bit slower for safety reasons — or a question of twiddling with the settings (there is an option for that, but I have no idea what to put there — is it a ratio, a percentage, what...?).
I don't know if European smart cars are the same as the US smart cars, but the speedometer in my 2015 electric drive appears to be around 6% too fast across the entire range of speeds.
 

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I don't know if European smart cars are the same as the US smart cars, but the speedometer in my 2015 electric drive appears to be around 6% too fast across the entire range of speeds.
I have no idea, either... but 6% sounds about right in my case, too. I haven't driven the car outside the urban limits, so I can't speak for 'the entire range of speeds' :-D but I'm definitely going to try it out on the motorway one of these days and see if the 6% is constant.

Also, to (partially) answer myself: the setting for adjusting the speedometer reading in DashCommand is a ratio, the default being 1.0, and the DashCommand manual sort of assumes that the ratio should be 'close to 1.0' (a 6% difference would mean 0.94 or 1.06, I don't know). They also suggest to use a GPS device to check the actual speed of the car, compared to what the speedometer says, and the manual has a simple formula to calculate the adjustment needed. I have no idea if my iPhone's GPS is accurate enough to read speed, but I can certainly do some experiments and see what is shown...
 

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I didn't know the speedometer was adjustable in that way. My thought on correcting it was actually to print a new speedometer backing that read 6% slower. If this is actually possible, then I am very interested!
 

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I remember reading on the forum here that the Smart uses speed input from all 4 tires and averages the result. The only way to make your Speedometer be spot on is to install 205/60 R15 tires all the way around. But for tires that size you must also install the Daystar lift kit. With the above tires my speedometer is spot on with GPS. So does it have an easier job if you have all 4 tires matching in diameter? Who knows. DCO
 

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Yeah, go with the rear tires since they drive the car. I think the speedometer difference is deliberate, most likely a liability issue where you don't want people driving too fast and either getting tickets or getting into accidents where they could be sued.

I also don't remember all of the sources I used for gear ratios, I know I prowled through a lot of sites.
Perhaps it was Fred's thread here: https://www.smartcarofamerica.com/forums/f4/rpm-s-vs-speed-2925/
 

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My apologies if I get my technical terms all wrong; to be perfectly honest with you guys, I'm a complete ignorant in all things car-related; I barely know to drive a car lol

Soooo... to figure out how accurate the speedometer on DashCommand is, I downloaded an app that measures your speed using GPS, and put it on an iPad mini, while looking at DashCommand on the iPhone, and checking on the Smart's built-in speedometer as well. It was a miracle I didn't have an accident lol (but at one point it was a really close call!!).

The GPS-based speedometer app managed during most of the time to lock on both GPS and Galileo satellites and was correct down to 5 metres — which is, I guess, the best I can expect to measure on a smartphone/tablet. What really impressed me is that it was spot on in sync with DashCommand — I tested up to 80 km/h (50 mph) and there simply was no difference whatsoever! Of course, the GPS-based system has some delay/lag, which DashCommand has not, but if I maintained the same speed for over a second, they would both be perfectly in sync! That was astonishing, I was expecting at least some difference, especially after reading your comments regarding the different tire sizes in the front and the rear!

However, the built-in Smart speedometer was another story altogether.

At very low speeds, the discrepancy was up to 10-12% — it consistently shows a higher speed than both DashCommand and the GPS speedometer. As @stuberman commented, this is possibly deliberate; my father had a car where this was clearly the case and he was aware that this was the brand's policy. However, as the speed increased, the discrepancy diminished — i.e. it's non-linear! — and at 80 km/h, it was down to about 6%, as far as I could see (it's hard to say just by looking at an analogue gauge!... especially when you're in the driver's seat and have to pay attention to traffic). I'm now actually curious to see if at higher speeds, say, 120 km/h (around 75 mph, the speed limit on our motorways), the discrepancy is even lower or even zero! (or who knows... negative... i.e. actually showing a slower speed than what the car is doing)

This actually makes not much sense. As far as I remember the rules around here, the police are often 'forgiving' within a tolerance of ±10%, knowing fully well that not all speedometers (especially those in very old, pre-OBD cars...) may be perfectly calibrated. This means that at higher speeds you get more tolerance (in absolute terms). Now the Smart's speedometer seems not to work that way: it exaggerates far more at lower speeds but gets much more precise at higher speeds — which doesn't seem logical to me, unless Smart figured out that people will be using their cars almost exclusively in urban settings and are just overzealous at lower speeds. Then again, a non-linear discrepancy is, IMHO, actually harder to build in (I don't really know how the gauge works, but I'd expect it to be like a clock, that either runs late or early, but does not speed up or down depending on the time of the day!), so I wonder what is going on here. In fact, DashCommand assumes that the car's speed is always incorrect by a fixed amount — i.e. a linear discrepancy — and that's the only way you can configure the app.

As said, I need to do more tests, possibly at higher speeds and for longer stretches... but there is something definitely weird going on.

A question from an absolute beginner in these kinds of things: is this something that my garage mechanic may be able to calibrate? I'm assuming, of course, that there might be a 'problem' with the speedometer (imagine that it has a stuck needle!). Perhaps this is all deliberately done by Smart and I should not worry...

Oh, and DashCommand does not report any (known) errors with the speedometer. I have no idea if there is a sensor for it as well. In fact, this whole galaxy of sensors that I had no idea that existed inside the car is completely flabbergasting to me :)

The problem with these amazing tools such as DashCommand is that you tend to be so overwhelmed by the data (I certainly am!!) that everything seems to be 'wrong' at some point. It's like going to the doctor after reading about all possible symptoms listed on Mayo Clinic's website — there are so many things that may be wrong with you that you don't trust the doctor when they say 'don't worry, you're fine'...
 
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