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I might crash if I keep staring at the Energy Monitor screen while driving!
How accurate is the speedometer?
the NX does have a lot of gadgetry let make you want to play with when you are driving... We are lucky we have the HUD compare to the US market. I dont look at the Speedometre anymore, most of the stuff I need to know are on the HUD, such as the energy monitor, GPS for direction and speed.
I will do a speedo test tonight. but my gut feeling is that the speedo is faster than you actually are.
in the past I have noticed I am doing 50-52km/hr but the GPS is showing I am doing 47-49km/hr
the NX does have a lot of gadgetry let make you want to play with when you are driving... We are lucky we have the HUD compare to the US market. I dont look at the Speedometre anymore, most of the stuff I need to know are on the HUD, such as the energy monitor, GPS for direction and speed.
I will do a speedo test tonight. but my gut feeling is that the speedo is faster than you actually are.
in the past I have noticed I am doing 50-52km/hr but the GPS is showing I am doing 47-49km/hr
For a more accurate speedometre test, if your highway has km markings (either signs or road markings), then drive at a steady 60 km/h (use automatic speed control) and start a stopwatch as your cross the initial km marker. When you get to the second marker, stop the timer.
The distance covered is 1 km and, driving at 60 km/h, your elapsed time should be 60 seconds (one minute).
If your time is less than that, then your speedometre is showing a lower speed than you are actually traveling. If your timing is more than 60 sec, then your speedometre is showing a higher speed than you are actually traveling.
For example, if your timing was 58 seconds, your actual speed was 62.07 km/h, not 60 km/h. If your timing was 62 seconds, your actual speed was 58.06 km/h.
Formula:
speed = distance ÷ time
So, for 58 seconds, the formula becomes:
Code:
speed = 1 km ÷ 58 secs
= 0.01724 km/s
Now, to convert that to km/h, simple multiply by 60 (to get from seconds to minutes) and multiply again by 60 (to get from minutes to hours). Therefore ...
Code:
km/h = 0.01724 km/s x 60 x 60
= 62.06 km/h
Finally, this procedure works for any distance at any speed. For example, if you know the start and end of a 500 m segment of road, you could use that. You can also drive at 30 km/h for the test—simply substitute the values in the formula and adjust it accordingly.
^^^ The speedometer is typically more optimistic than the HUD which means it will usually indicate a slightly faster speed than actual. When I had the summer 22" wheel/tires which had a larger rolling diameter by about 3.5% over the 18" OEM wheel/tires, it rotated "slower" making the speedometer virtually a match to what the HUD displayed. Now that I'm on the 18"s, at 100 kph on the HUD, the speedometer indicates 102-103 kph without parallax factors.
PS. The RX's HUD was GPS and gyro-sensor based. I believe the NX is no different. from my experience.
the NX does have a lot of gadgetry let make you want to play with when you are driving... We are lucky we have the HUD compare to the US market. I dont look at the Speedometre anymore, most of the stuff I need to know are on the HUD, such as the energy monitor, GPS for direction and speed.
I will do a speedo test tonight. but my gut feeling is that the speedo is faster than you actually are.
in the past I have noticed I am doing 50-52km/hr but the GPS is showing I am doing 47-49km/hr
I am so happy that I optioned it up with a HUD. I currently drive a Honda Civic with a high-mounted LED speedometer and after using it, I can't drive any other car with analogue dials.
I like the energy monitor on the central display on the console. It's nice and big. Hopefully the small screen in-between the dials will also be sufficient.
Originally Posted by corradoMR2
PS. The RX's HUD was GPS and gyro-sensor based. I believe the NX is no different. from my experience.
That's very interesting. I would have though that the HUD would get the data from the computer system, the same system that the analogue speedometer gets its speed from. I didn't know it used the GPS.
If the GPS is more accurate, why doesn't the analogue speedometer use that too?
I am so happy that I optioned it up with a HUD. I currently drive a Honda Civic with a high-mounted LED speedometer and after using it, I can't drive any other car with analogue dials.
I like the energy monitor on the central display on the console. It's nice and big. Hopefully the small screen in-between the dials will also be sufficient.
That's very interesting. I would have though that the HUD would get the data from the computer system, the same system that the analogue speedometer gets its speed from. I didn't know it used the GPS.
If the GPS is more accurate, why doesn't the analogue speedometer use that too?
the central monitor is nice, I use it as a map if I am in a new area. my central monitor "home" is set to default where left side of the screen is the map, top right is the music, bottom right is the fuel consumption. I keep the small screen between the dials as the energy monitor, its sufficient.
I think the GPS is more accurate, but there is a lag. As you speed up, the GPS lags by a second or two where the speedometer does not have this lag. In steady state driving, the GPS should be accurate. I have not checked the Lexus, but all Toyotas that I've owned in the past were off by 2 - 3 mph at highway speeds. All indicated a higher speed than actual. The Fords I've owned were only off 1 - 2 mph.
the central monitor is nice, I use it as a map if I am in a new area. my central monitor "home" is set to default where left side of the screen is the map, top right is the music, bottom right is the fuel consumption. I keep the small screen between the dials as the energy monitor, its sufficient.
Ahh I see. That is a very good setup I assume I can set what each corner does?
I will be sure to use your tips.
Originally Posted by NXOwner
Caveat: Many GPS units are unable to account for changes in vertical direction, so may be less accurate if you are travelling up or down a steep hill.
Yes, you are very right. However, I think that GPS can also account for the elevation and adjust the speed accordingly.
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I just came back from my dealer today, they said the car will be coming first week in Jan so I still have to wait until 2016!