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You don't need a tach on a fixed ratio gearbox. A speedo is basic equipment for roadworthiness in many places...that gets you an odoneter in most cases.

Otherwise, an hours meter is useful in place of the odo for maintenance & valuation

Buyer: "how money miles/hours on it since the conversion?"
You: "I have no idea...."
 

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Converting their tach to a speedo doesn't work. Clearly, there's a stack of metal plates in China waiting for white silkscreen.

So much awful there.

I'd use a tach plate for a Speedo, marked accordingly

Battery temperature needs a red zone above 70C (or whatever your cell freakout temperature is) unless you use tricolor LEDs in the holes.

Battery SoC needs a red at 10% unless tricolor LED in hole.

Amps needs green to max continuous, yellow for peak, red for yikes.

Need an outlet temperature for DU cooland/oil and inverter outlet coolant temperature.

I prefer the cat pee yellow vs bird poop white for the lettering/markers, but that's just a matter of one of us lacking personal taste 😂
 

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According to tests from NASA, an 18650 cell doesn't light off until 120C on its case.


If you're trying to hit max rate charging, you're running the cell cases at 45C-50C for at least a dozen minutes. Half scale would not work, as you'd get zero visibility to a creeping heatup during charging due to a failed cooling loop.

Depending on your sizing and method, of cooling, I suspect you could see excursions to 60-70C during charging. So top end, 90C would be my choice. Which is still not 4th of July fireworks, according to NASA.

At the other end, to at least zero degrees C.

So, for my cars it would be

maybe orange -30-0C
yellow 0-15C,
green 15-xC
yellow x-60C with a "SC" mark at 45 or green from 40-60C
orange 60-90C

x is TBD - maybe someone has a rational basis for its bottom end value. Is yellow warranted during regular summer days in places like Thailand, where Bjorn Nyland found the cars to be running near peak efficiency in a place that normally is 35-40C in summer? I submit it's 40C. And 40-60 is SC*

*and super scoot current mode
 

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I live in Denmark where hour is time so it is called km/t.
The yellow and red are because it was made such original on datsun z.
You can also see my speedometer at the top of the thread there is a line from 100km / h and up

View attachment 127827
One of the Scandanavian countries did traffic fines as a percentage of annual income, so is the red more than a year, then?
 

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I make a canbus conversion from theNissan leaf canbus an send it to the gauges.
Do you have a comprehensive list of the gauge CAN messaging as well as Leaf CAN messages you could either link or post here, so when people want to hook up their gauge faces they can cobble up scale converters etc?

A lot of Leaf conversions in this forum (too puny for me)...it's the Warp9 of the 2020's
 
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