speedo accuracy

[robtt09]

Very impressed with accuracy of speedo on my car! According to my Snooper Sapphire it overreads by only 1mph at 80mph!That is on a straight and flat A road so believe the Sapphire will be accurate.

[Plife]

Yes come to the same conclusion against my Sat Nav. Guess that is pretty accurate.

[ScottyUK]

That's good news. I've yet to try it yet. I've heard that somewhere in MMI you can display the GPS speed if you have SatNav but I haven't done this yet.

My B6 S4 was showing 164 on the dash which exactly matched the electronic speed trap.

[A1287210]

I posted a little message about this a while back saying that I found that even going at bang on 50 mph through the roadworks I seemed to be flying past everyone. Maybe very accurate. I would be very interested in the GPS speed. I'm just waiting for a stretch of road when I can really stretch the legs of the 143..cos the speedo says I goes up to 180 mph

[rd1]

I found that my speedo is under reading by 2mph compared to my Novus Rider cam spotter. I also found that I was always overtaken through the average cams when on cruise.
I would be interested to know how to turn on the MMI GPS if poss as this would check the novus out as well.
Roger

[A1287210]

I think that it may be a myth,,,,,,