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muddyboots
16-05-2003, 16:56
Afternoon all

Recently I was playing with my handheld GPS to see how accurate the Ibiza's speedo was.

The speedo in my last car, a Rover 220SDi, over-read by 10% - IE if the speedo says 70, it was really only doing about 63. I checked on various occasions and always got the 10% error. (Unfortunately it said it had done 10% more miles than it really had, too !)

I tried the same test in the Ibiza, and the speedo is absolutely bang on.

So now when I drive past speed cameras etc I have to take the speedo as being true, without driving to the 10% safety margin I always used to have !

I think a lot of cars must over-read by a fair margin, as when in the Ibiza, it seems many people drive a few mph slower than the limit, not realising their speedos are lying to them. In the Rover it always seemed that people were at the limit.

Anyone else ever tried testing their speedo ?

prc
16-05-2003, 17:24
Normally it is about 10%, I've picked up around 6% on the toledo. You will get differences even as the tyres wear. Wheel diameter with new tyres is almost 15mm more.

Fen
16-05-2003, 17:34
I've found them more accurate than I expected. My Ibiza was very close to spot-on with the 17's, but was about 4% optimistic on the standard wheels.

My 944 Turbo is close to bang on as well with its 18's and my cab is about 2.5% out on standard 16's.

aceman
16-05-2003, 19:57
well, my original speedo used to read bang on 80mph at 2000rpm in 6th but it then developed a fault (wouldn't return to zero) and I had to get it changed under warrenty. Now at 2000rpm it reads 75mph so which was correct ?

If I go by the local speed warning sign outside the local school I can now trigger it at 31-32mph whereas before it was 33-34mph !

Gleistung
17-05-2003, 10:11
No news here...the new Ibiza´s speedo is extremely accurate, most units have no error at all!

Mark Hodder
18-05-2003, 21:31
I posted this info in the Cupra R forum too:

Ibiza TDi speedo is out by about 2mph all the way across the speedo. Managed a GPS top speed of steady 135mph on the Autobahn.

Leon R is 10%+ out, leading to very interesting top speed on the speedo on a recent trip to the Autobahn. The GPS soon brought the truth to light!

Mark

Black Leon R
Red Ibiza TDi Sport