speedometer accuracy
#16
Originally Posted by gfmiller
Before going much further you should check your speedometer the old fashion way; timed over a measured distance. There are still locations here in the US that have "measured" miles along the Interstates for this purpose. Using our obsolete but adequated system of measures, a measured mile at 60 miles per hour takes exactly 1 minute.
I think GPS is a wonderful invention, but question its accuracy for checking speedometers.
I think GPS is a wonderful invention, but question its accuracy for checking speedometers.
#17
Originally Posted by GEE35X
You can't get a much better check than a WAAS enabled GPS.
When I changed tire to a set of exact size as the factory tires but a differnet brand (Michelins) my GPS showed me going slower than my speedo said. So as I've said before not all tires are created equally.
#18
Originally Posted by kring
I suspect the car is dead-on accurate, I question the accuracy of the metric system in general, it's a fad. As long as beer is ordered by the pint, no one's going to adopt the metric system
Score: Metric System 0, Imperial System 1.
Imperial system is so easy, 1 gallon = 1 gallon of gas, not 4.546 litres... I'll stick with my Pecks, stones, tons, bushels and furlongs.
![Smilie](https://g35driver.com/forums/images/smilies/smile.gif)
Score: Metric System 0, Imperial System 1.
Imperial system is so easy, 1 gallon = 1 gallon of gas, not 4.546 litres... I'll stick with my Pecks, stones, tons, bushels and furlongs.
![Roll Eyes (Sarcastic)](https://g35driver.com/forums/images/smilies/rolleyes.gif)
#20
#22
I've checked my speedometer via GPS, mile markers, and those road side speed sensors the police put up to show how fast you are going. Within 1mph according to all 3. My truck too.
My previous car would be going at 80-82 when it showed 75. The car before that would be going a little slower than the speedometer indicated.
My previous car would be going at 80-82 when it showed 75. The car before that would be going a little slower than the speedometer indicated.
#23
#24
My 04 Audi S4 did the same thing,, read faster then you where going
And the dealer did nothing,,, because they can't,,, thats the way audi did things, at least back then.... Its was almost 3.5 MPH @ 60..
However my 07 X appears to be like most here,, close to spot on, or less than 1 mph off.....
![Mad](https://g35driver.com/forums/images/smilies/mad.gif)
![EEK!](https://g35driver.com/forums/images/smilies/eek.gif)
#25
#26
Originally Posted by Triton3.5
My 04 Audi S4 did the same thing,, read faster then you where going
And the dealer did nothing,,, because they can't,,, thats the way audi did things, at least back then.... Its was almost 3.5 MPH @ 60..
However my 07 X appears to be like most here,, close to spot on, or less than 1 mph off.....
![Mad](https://g35driver.com/forums/images/smilies/mad.gif)
![EEK!](https://g35driver.com/forums/images/smilies/eek.gif)
#27
Speedometer problem
Well guys, I am also having the same problem with my G35sport 07. I have stock wheels at proper PSI and I also have between a 10 and 12 KPH diference in the speed across th eboard with the car registering much higher... I am going to the dealer next week to check this out... I also have lots of crashes on the Navi/onboard computer system when I use my bluetooth with a Moto Razr phone....The software in the car is not stable when it comes to the bluetooth...
Arun..
Arun..
#28
GPS is inaccurate. The triangulation that the sats do is shoddy at best. Unless you're using a high priority military receiver, the GPS guesstimates your position.
I'm a fanatic about speeding tickets (thanks to my through-the-roof insurance) so one day a buddy and I used his radar gun to test my speedometer. It says I'm going 2 mph faster than I am, at all speeds.
On another note, I've never heard of a speedometer being off by 10-12kph, that's insane! And my navi has never crashed either, though I do have some gripes about BT (though I blame the BT nuances on the experimental Windows Mobile 6 build that my phone is running).
I'm a fanatic about speeding tickets (thanks to my through-the-roof insurance) so one day a buddy and I used his radar gun to test my speedometer. It says I'm going 2 mph faster than I am, at all speeds.
On another note, I've never heard of a speedometer being off by 10-12kph, that's insane! And my navi has never crashed either, though I do have some gripes about BT (though I blame the BT nuances on the experimental Windows Mobile 6 build that my phone is running).
Last edited by KLASiKAHL; 04-12-2007 at 02:06 AM.
#29
#30