Speedometer accuracy...
Thread Starter
Race Car
Joined: Aug 2001
Posts: 4,922
Likes: 1
From: London, UK
Speedometer accuracy...
I have at last managed to get a Snooper S6R Neo from Costcc. Whilst out and about 'testing' it, I thought I would also gauge the accuracy of my speedo. Interestingly (perhaps), the speedo itself is 100% correct at all speeds up to 100mph, whilst the OBC shows around 4-5mph higher than actual speed. I thought all speedos read a little high?
I am assuming here that tracking my speed via GPS is accurate.....
I am assuming here that tracking my speed via GPS is accurate.....
Three Wheelin'
Joined: Mar 2003
Posts: 1,402
Likes: 1
From: New Jersey
My speedometer is around 10% high I would estimate as well, although I don't know if that is throughout the measurement range- 120 mph vs. 40 mph for example. Based on the radar traps they occasionally have here in the US, where there is a sign- "Speed limit x", then under it "your speed". Usually when I see these things, I accelerate to make the numbers flash higher and higher before I pass it 
More seriosly, when I'm not accelerating, I'll hold say 50 mph and the sign will say 45 mph. I don't know how accurate these signs are, as cops don't actually use these to write tickets- its more of a warning to bring up awareness of speed limits on a given road- the signes are on wheels & they move them from road to road. I think the speedometer in my beetle (also VDO) is more accurate, but that rarely gets past 70
More seriosly, when I'm not accelerating, I'll hold say 50 mph and the sign will say 45 mph. I don't know how accurate these signs are, as cops don't actually use these to write tickets- its more of a warning to bring up awareness of speed limits on a given road- the signes are on wheels & they move them from road to road. I think the speedometer in my beetle (also VDO) is more accurate, but that rarely gets past 70
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Rennlist Member
Joined: May 2002
Posts: 3,605
Likes: 4
From: Bologna, Italy
My speedo seems to over read by 10%. It seems to be accurate at 30mph, but when doing 100mph, my Roadangel only reads 90.
The down side of this is that I find myself looking across to it for my speed rather than looking at my speedo. Not good!
The down side of this is that I find myself looking across to it for my speed rather than looking at my speedo. Not good!
Three Wheelin'
Joined: Mar 2003
Posts: 1,402
Likes: 1
From: New Jersey
Andy- pisses me off too. I have the same issue with my BMW- I'm always correcting in my head say 10% lower for the speed. On the BMW I can hold an indicated 90 mph, and hit average speed reset on the computer, then the car's average is something like 84 mph or 83 mph or something. Seems pointless to go through the trouble of having fancy "VDO" guages that are consistently inaccurate.... I think the car manufacturers do this through, not the speedometer company, in fairness to VDO.
