How accurate is the speedo at high speed? Pretty bad I'd imagine. When tthe needle right round off the clock (past an indicated 150mph) how fast do you think it's actually going? If I plugged in my TomTom would that be closer to the real speed or are they too a long way off?

How accurate is the speedo at high speed? Pretty bad I'd imagine. When tthe needle right round off the clock (past an indicated 150mph) how fast do you think it's actually going? If I plugged in my TomTom would that be closer to the real speed or are they too a long way off?

Your tom tom should be pretty accurate. With my clock showing an indicated 120mph the tomtom was saying i was doing 110ish. I would imagine at 150mph you probably looking at a disparity of 15-20mph.

Edited 3 January, 201115 yr by Simonbt

i think the sat navs are rubbish at tellin the true speed, i dont trust them.

My road angel seemed accurate in my old zr speedo showed over 120 but road angel showed 114

i think the sat navs are rubbish at tellin the true speed, i dont trust them.

The SatNav should be very accurate indeed, but it may well lag a little as it's doing the calculation based on position updates.

At the OP, when I was absolutely wound around the clock (150mph+) I was actually doing 134mph. The aerodynamics on the cars, coupled with the stratospheric gearing mean that it's very hard to get much more than that standard, and the best remapped ones only do in the low 140's.

That's still very fast and quite scary really.

not entirely the same car...but ~145mph on the clock of my mk4 diesel Ibiza was 141mph on the satnav

not entirely the same car...but ~145mph on the clock of my mk4 diesel Ibiza was 141mph on the satnav

Yes, that has 17" wheels on I think. I think mine would be more accurate now as it has 215/40/R17s on and the speedo is very nearly bang-on at 70mph.

Yes, that has 17" wheels on I think. I think mine would be more accurate now as it has 215/40/R17s on and the speedo is very nearly bang-on at 70mph.

yep

Cheers, does anyone know if there's any clocks that will fit in the vRS which has a higher speed reading? It goes off the clock but still keeps pulling so don't actually know what speed it's indicating.