What to use to tune my NB's speedometer?
#5
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Okay, I'll break this down for you.
My speedometer reads a different speed than I'm going, as verified by the GPS.
Many cars are not very accurate with that setting. Most read high.
Mine is reading high enough to cause issues, that I wish to resolve.
To bring the displayed speed in line with reality, is called calibration. This means that the speedometer and the GPS should say about the same speed.
In order to do this, there are signal modifiers that plug into the electric signal of the speedometer and alter it so that the displayed speed can be accuratized.
That's what calibration means.
I'm asking for the thing that plugs in. Which would be the best, where to get it. It's something you buy. Plug in. Program. Problem fixed.
My speedometer reads a different speed than I'm going, as verified by the GPS.
Many cars are not very accurate with that setting. Most read high.
Mine is reading high enough to cause issues, that I wish to resolve.
To bring the displayed speed in line with reality, is called calibration. This means that the speedometer and the GPS should say about the same speed.
In order to do this, there are signal modifiers that plug into the electric signal of the speedometer and alter it so that the displayed speed can be accuratized.
That's what calibration means.
I'm asking for the thing that plugs in. Which would be the best, where to get it. It's something you buy. Plug in. Program. Problem fixed.
#10
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What size are your tires? A different tire diameter will affect the speedo.
Which rear end ratio sender is physically installed? You may not have changed it, but did you buy the car new? Maybe the PO changed the sender and put in the wrong one? It's one bolt to pop it out and count the teeth on the gear.
Is your odometer correct, or is it also off? Usually those are calibrated a lot more accurately than the speedometers. So if your odometer is right, but your speedometer is high, then you probably just have a speedo that's not displaying the input signal correctly. If that's the case, then modifying the input signal will make the odometer update incorrectly.
--Ian
#12
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This is the first I've heard of calibration. I thought everyone just swapped in various tooth count gears. I have one or two around the garage.
If you find out how many teeth you need to get it spot on and I happen to have one I'll trade you.
If you find out how many teeth you need to get it spot on and I happen to have one I'll trade you.
#13
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What's that?
Miata speedometers are not generally off by 10%, so why not focus on trying to find the broken part in your system rather than band-aiding it by modifying the electrical signal?
What size are your tires? A different tire diameter will affect the speedo.
Which rear end ratio sender is physically installed? You may not have changed it, but did you buy the car new? Maybe the PO changed the sender and put in the wrong one? It's one bolt to pop it out and count the teeth on the gear.
Is your odometer correct, or is it also off? Usually those are calibrated a lot more accurately than the speedometers. So if your odometer is right, but your speedometer is high, then you probably just have a speedo that's not displaying the input signal correctly. If that's the case, then modifying the input signal will make the odometer update incorrectly.
--Ian
What size are your tires? A different tire diameter will affect the speedo.
Which rear end ratio sender is physically installed? You may not have changed it, but did you buy the car new? Maybe the PO changed the sender and put in the wrong one? It's one bolt to pop it out and count the teeth on the gear.
Is your odometer correct, or is it also off? Usually those are calibrated a lot more accurately than the speedometers. So if your odometer is right, but your speedometer is high, then you probably just have a speedo that's not displaying the input signal correctly. If that's the case, then modifying the input signal will make the odometer update incorrectly.
--Ian
#15
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Maybe you can have you MS do it if you build the circuit.
https://www.miataturbo.net/suspensio...or-give-58383/
or
http://www.dakotadigital.com/index.c...roduct_id=126/
https://www.miataturbo.net/suspensio...or-give-58383/
or
http://www.dakotadigital.com/index.c...roduct_id=126/
#17
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Who says there is a gear that will be accurate for her diff/tire/transmission setup? Figuring out that is step 1 I guess. But to be extremely accurate signal modification may be the only way. If "in the ball park" is good enough a gear swap may work.