To those of you with GPS speedos

TrickyWicky

agrinnall wrote: »

Where can I get one of these sat navs that calculates what your fuel consumption is? :rotfl:

Lol you know what i mean

mikey72

Wig wrote: »

So the Mini and the Renault are both underreading on the car speedo?
Oh dear. Is that a 1980s mini?

Got that backwards didn't I?

Stephen_Leak

Current 2004 Fiesta. 3mph (ie. GPS = 27, speedo' = 30. GPS = 47, speedo' = 50. GPS = 67, speedo' = 70).

Old 1997 Mondeo. 10% (ie. GPS = 27, speedo' = 30. GPS = 45, speedo' = 50. GPS = 63, speedo' = 70).

Electr0n

Isnt the vehicle speedo sposed to read more than "actual" speed anyway ....

ie ..
the speedometer must never show an indicated speed less than the actual speed. However it differs slightly from them in specifying that for all actual speeds between 25 mph and 70 mph (or the vehicles' maximum speed if it is lower than this), the indicated speed must not exceed 110% of the actual speed, plus 6.25 mph.

For example, if the vehicle is actually travelling at 50 mph, the speedometer must not show more than 61.25 mph or less than 50 mph.

The_ICT_Engineer

It depends if you want the speed through the water or over the ground. Even than it depends on the flow and direction of the current

Notmyrealname

Current Mondeo says 70, Satnav says 68
Capri said 70, Satnav said 65.
Mates Vectra said 80, Satnav said 70.

Wagon said 56MPH, tacho calibration test said 55.5MPH - tyres half worn.

Electr0n

The_ICT_Engineer wrote: »

It depends if you want the speed through the water or over the ground. Even than it depends on the flow and direction of the current

wouldnt the OP of mentioned "knots" ?

TrickyWicky

The_ICT_Engineer wrote: »

It depends if you want the speed through the water or over the ground. Even than it depends on the flow and direction of the current

What on earth are you on about?

The op isn't asking about driving a boat down the river thames. The op asked a simple question, when driving at a steady 70, what does your GPS speed say.

You have to go and over complicate it to try and look clever and instead you've made yourself look silly.

The_ICT_Engineer

Electr0n wrote: »

wouldnt the OP of mentioned "knots" ?

On the Inland waterways mph or Kph is used. At sea it's in knots ( nautical miles) as is the case with air travel.

Speeds measured with a GPS differ from those measured by other means in that they are Speed Over Ground (accounting for the effect of current) while the others are Speed Through the Water, which does not account for current.

ie: The log by which a log with a knotted line attached which is paid out over the stern in a given time, The number of knots passed giving the speed through the water, Hence the term 'knot' for a nautical mile.

vax2002

It measures flat distance, unfortunately roads have hills and dips, so sat navs are often a bit low.