Are they really that inaccurate?

[ChrisFitz]

Was thinking that the speedo on my Gallardo was under reading somewhat when coming back on the motorway the other day.
So took it out and measured it against a sat nav and also my Scoob.
Found it to be 10% over reading exactly at all speeds including ones into 3 figures (obv done on a private track!).

Queried at dealer and told all Gallardo's do that! Amazing!

Did some searching on the internet and it does seem to be a common fault.

Anyone else with a Gallardo got the same problem. Seeing as Lambo won't sort it out, any other routes available.

Surely being digital it must be something that can be adjusted.

Ok, at low speeds but 10% out at a theoretical 140 would be really 126.

Find the response a bit naff really. £100K + car and it can't accurately tell me how fast I'm going!

[paulqv]

Hi
Virtualy all cars speedos over read. It is very rare to find ones that are absolutley accurate. Legally they only have to be accurate to 10% over in europe.
Old guys like me will remeber that it was used by Ford as an 'unofficial' marketing tool in the 70's to make their cars seem faster! Hence the legendary 120mph 1.6l cortinas etc!!!
Depending on where the drive is taken from accuracy could more easily be achieved on modern cars.
When it was off or related to the number of rotations of a driven wheel there could be variations due to tyre wear, temp etc. Most tyre manufactures tech guides gave diameter as varying by +/- 2%!
In short, not a lot you can do and it's legal!
Hope this helps
Paul
xxx

[AndrewD]

If it makes you feel any better, the speedo on my SV over reads also, by around 7%

[XXVIII]

... and in the world of wonder that is Gobbon Broon's Great Ukland, the last thing you'd want is a speedo that says you're doing less mph than you are ...

I like the idea of casually mentioning to your dinner guest that whilst the speedo said you were doing over 180 mph you may only have been progressing at 162, so (s)he'd not want to take that too seriously.

Edited by XXVIII on Tuesday 21st July 16:04

[Gring]

My Maserati's speedo is spot on up to 120 compared against my road angel. First car I have ever come across to be accurate.


http://www.pistonheads.com/sales/1145052.htm

Edited by Gring on Tuesday 21st July 16:06

[al1991]

Gring said:

My Maserati's speedo is spot on up to 120 compared against my road angel. First car I have ever come across to be accurate.


http://www.pistonheads.com/sales/1145052.htm

Edited by Gring on Tuesday 21st July 16:06

I've noticed on the pictures of your dials in the ad it looks as though it is reading 20mph? I have noticed it on a couple of other Maser ads too, is it the angle? Sorry for the o/t.

[Gring]

al1991 said:

Gring said:

My Maserati's speedo is spot on up to 120 compared against my road angel. First car I have ever come across to be accurate.


http://www.pistonheads.com/sales/1145052.htm

Edited by Gring on Tuesday 21st July 16:06

I've noticed on the pictures of your dials in the ad it looks as though it is reading 20mph? I have noticed it on a couple of other Maser ads too, is it the angle? Sorry for the o/t.

On tickover they stick at about 10mph until you start moving.

[ChrisFitz]

paulqv said:

Hi
Virtualy all cars speedos over read. It is very rare to find ones that are absolutley accurate. Legally they only have to be accurate to 10% over in europe.
Old guys like me will remeber that it was used by Ford as an 'unofficial' marketing tool in the 70's to make their cars seem faster! Hence the legendary 120mph 1.6l cortinas etc!!!
Depending on where the drive is taken from accuracy could more easily be achieved on modern cars.
When it was off or related to the number of rotations of a driven wheel there could be variations due to tyre wear, temp etc. Most tyre manufactures tech guides gave diameter as varying by +/- 2%!
In short, not a lot you can do and it's legal!
Hope this helps
Paul
xxx

Sure I understand the legalities of it over reading as opposed to under reading. Was interesting comparing it to our 2 other cars which were approx 3% & 4% over, and a subaru and mini respectively. So as they can seem to achieve it, I thought a car costing 8 times as much would have no problems either. Also, both of the above offer to tweek them if required. Not offered by Lamborghini.

[fade2grey]

yup, my gransport was bang on the money all the way up past 140 according to tom tom. A little too accurate down at 30 if you know what I mean.

[Gring]

Inacurate speedo's is one of the reasons you get annoying codgers driving along at well below the speed limit.

[Tadek]

Hi Chris, your right, our Lambo speedo is not that accurate, but the Corvette Z06 is spot on. How is it that the Americans can get it right and us Europeans can't?

[cayman-black]

Plus i struggled to get my gallardo past 194mph on the speedo, was really only about 180 then. 996 turbo was faster!

[andrew.]

fwiw my sl's 5% optimistic relative to my satnav, but the 911's 1% over

[marine boy]

Tadek said:

Hi Chris, your right, our Lambo speedo is not that accurate, but the Corvette Z06 is spot on. How is it that the Americans can get it right and us Europeans can't?

I would gladly swop a Corvette or any of America's home built finest with an accurate speedo for a Ferrari, Porsche, Zonda, Maserati, Audi R8, Lamborghini, Bugatti with an inaccurate speedo!

Sometimes sacrifices have to be made when living the dream, chin up and work around it or if it's that big a problem chop it in for a Z06.

[AyBee]

Cheapest option is probably to get something with a large GPS speedo readout like the roadangel, then for when the speed you're travelling at is important then you can see what the over-read is....

[BlueMR2]

So if your services are every 10k miles and your speedo over reads by 10% then every 9k driven is 10k on the odometer.

Wonder why they would do that .

[ChrisFitz]

BlueMR2 said:

So if your services are every 10k miles and your speedo over reads by 10% then every 9k driven is 10k on the odometer.

Wonder why they would do that .

From what I've read the odometer is pretty much bang on. It's the speedo that is out.