I have put about 1000 miles on my car this weekend only and i have noticed that with the 2 GPS's that i have both say that i am going 2 miles slower than what the needle says. This is on stock tires and rims soo yeah. Just figured that i share that with you.

Oh and at 120 on the GPS, it was saying 122.5 on the guage (line between 120 and 125). and the same thing at the rest of the speeds. I knew that they were off, but i noticed this and wanted to post

 

the GPS is not going to be perfect. if you are using a laptop with a usb gps, its going to be off a little. I have the same thing, and its just the lag between transmission of data, and output. Everything is fine....you dont even have aftermarket rims..so no worries.

 

No, all cars are slightly off. The GPS is gonna be more accurate since its digital, the speedo is mearly a mechanical needle over some dashes so there is a small error.

And if your tires are anything but the same model as what came from the factory, that can have an affect as well.

 

Mine is off by about 5 MPH against the radar signs

 

every time i got by those, mine speedo says i'm going 2 mph over what the radar says.

 

yeah i forgot about that. mine was saying that i was 2 miles above what the radar was showing.




and i was using one USB laptop one and TomTom, both stating the same speed.

 

Yah, mine says that I am going 2 MPH slower than I really am by radar. Must be a way to help control speed? You think you're doing 5 over instead you're doing 3 over. Kinda like setting your clock 2 minutes ahead.

 

I think my wheel speed sensor is jacked up

 

The speed difference between my gps (garmin qwest) and speedo is bigger at high speeds. At 30mph the gps says 28. At 100mph the gps says 95. I've used the gps in a couple other cars and it has been almost right on (+/- 1mph)

 

U'll have that, it's in space man