Speedo reading slow

[AndyLala]

OK, I have the definitive answer - err I think.....

I took the dash front off and armed with a borrowed GPS unit spent an hour driving up and down the M5 at various speeds. The (electronic) speedo needle can be carefully repositioned by moving it against the stop each end. For the low end you have to raise it over the dial stop needle - there is another stop in the works somewhere.

3.0ltr diesel auto on std big tyres (265/70 x 15) I got the following:

in lockup 4th gear the gearing is near enough 27 mph/1000 rpm.

So:

2000 = 54 - (pretty much where the lockup comes in)
2500 = 68
3000 = 81
3500 = 95
4000 = You're nicked son

Cheers

Kev

And thanks for all the feedback.

Can you elaborate on respositioning the needle, I am convinced that I have put it back on wrong. 'and that might be causing the needle not to move at all...
andyL

[dirtydog]

shows how much better 3.0 is for cruising... be lucky if im at 70mph @3000rpm! (dials are out though cos im on 31's)

[Gizmo]

My SAT-NAV records my speed to be slower than the speedo. Im running 31x10.5x15 tyres.

Same here..been keeping an eye on the needle of late since acquiring the GPS unit. Depending upon the speed it varies between 5mph and 10mph at the top end

[riddler]

gps

[riddler]

gps

Hey exmee, is the gps unit 'stand alone' or is it wired into your truck? Is it wired to your trucks speed sensor?

[exmee46]

Gps

Just a hand held unit. I only used it to calibrate the speedo. Its now within +/- 2mph up to 90 then starts to overread a bit. I've had it up to 105 (ie end of the scale) - and it still feels like it wants to pull more - its certainly geared for it

Cheers

Kev

[exmee46]

Can you elaborate on respositioning the needle, I am convinced that I have put it back on wrong. 'and that might be causing the needle not to move at all...
andyL

More details in this thread Andy http://www.yotasurf.co.uk/forums/showthread.php?t=9824

Cheers

Kev

[Predictable Bob]

Evening All !

Gordon Brown gave me a little present before Chrimbo and herself told me to invest it in Tom Tom Go - something to do with reducing friction when travelling together ....

anyway according to the magic box both my Surf and the runabout (Focus Estate) have speedos that are a little optimistic - at an indicated 65mph TTG says they're doing 60 - the optimism reduces gradually with speed so that they are both fairly well spot on at 30mph.

Interestingly enough driving through the M25 roadworks using TTG for speed indication I actually overtake a significant amount of traffic which suggests that other cars speedos are optimistic too. Wonder if it's a manufacturers ploy to make fuel consumption appear better ?????

Oh yeah - I've tested the accuracy of TTGs speed indication on the M25 traffic cameras - no flashes at all from known working cameras - confess to being a little twitchy the first time I tried it !