How accurate is my speedo?

[si_hartlepool]

I don't know if it's because i came from a leon with a 6 speed box (lower revs and less engine noise in 6th) but at 70mph in my 182 it feels like i'm flying.

Are the speedos accurate or are my senses playing tricks on me?

 

[dmallett]

Get a decent sat nav and compare.
For example. When my clio says im doing 70 the satnav says im doing 65.

 

[DanFreemanPhoto]

Or drive alongside one of those big French MPV things with large digital speedo displays.

 

[mugglesquop]

smaller (less well built) cars do feel faster as you have more noise and are lower to the ground etc.

a original mini at 60 feels like my audi estate at 120 (private road)

 

[si_hartlepool]

Shame the factory sat nav doesn't have a speed display. Suppose i'll have to compare it using a normal sat nav. Either that or go Picasso hunting on the way home haha

 

[Goodj]

about 6% out I find.

but it will change depending on wheels and tyre conditon

 

[Knuckles]

Find one of those high score/your speed signs... The digital one that gives you a read out.

Mines 2mph slower than it says

 

[si_hartlepool]

Find one of those high score/your speed signs... The digital one that gives you a read out.

Mines 2mph slower than it says

haaaaa

 

[Tony Hunter]

They are all set lower to save your licence,put on the cruise control and it will differ to the speedo.

 

[laberridge]

you speedo only has to be accurate up to 30mph, after that the fast you go the more inacurate its going to become.

 

[Goodj]

They are all set lower to save your licence,put on the cruise control and it will differ to the speedo.

even CC is a percentage out.

But, to be fair, it's so minimal you're not going to save hours of your life by using your GPS speedo to stick to the limit.

Unlike, say, some old supercars that would say you're doing 120 when you've barely broke a ton.

 

[Steven103]

Have you got standard sized wheels/tyres? (205/45/16) If not the speedo will most likely be messed up as the equation most ECUs use to find speed has an r, for wheel radius, in it. Change r without telling the ECU and your speedo is wrong!

As I said, this is how most cars do it. Maybe Fred/Danny/etc can tell us if the clio has a way of getting around this (e.g. some cars calculate speed from RPM as well as wheel speed in order to get an average reading in the event of errors)

 

[laberridge]

heres a calc to work out your speed with different sized rims. http://www.kouki.co.uk/utilities/visual-tyre-size-calculator

 

[si_hartlepool]

standard wheels and tyres lads!

It's alright...it was just my senses messing with me because i came from a bigger/quieter car

Cheers for your comments

 

[fletch8]

my cruise control will say 70 for example however my dial says around 73/74?