Recalibrate speedo?

[Error404]

I want to recalibrate my speedo if its at all possible, so it reads right rather than 10-15% under - is it possible?

[QuattroFever]

fit bigger wheels

helpful as always

[Error404]

haha, yeah thats the ghetto way of doing it

[s2_wot]

I got a few interesting answers when I asked the same question some months back.

http://www.s2forum.com/forum/showthread.php?t=50057

HTH

[Rusty]

A set of S2 dial faces in CQ clocks will give you and over-read of about 5%

[Error404]

S2 & 20vCQ clocks are the same, just different colour. I've got S2 clocks anyway, and they overread by about 10-15%

[varia]

i noticed that, but why ?

[Rusty]

S2 & 20vCQ clocks are the same, just different colour. I've got S2 clocks anyway, and they overread by about 10-15%

Nope, they're not, the CQ is 5% different, just look at the position of the 160 marker, it's further round on the CQ

[Error404]

Those aren't 7A clocks dude, they red line at 7k

[Rusty]

I never said they were 7A, just CQ. Can you post a pic of your speedo up please, I'm interested

[s2_bo]

Theres quite a few different speedos but i seam to remember the 7a ones where the same.
I even found a UN4 cluster the other day that i had left over with 160mph range.
Very unusual as the UN4 ones are usually 140mph.

I think the easiest recalibration would be a resistor in the speed sensor wire.
Other then that i dont think there is any physical adjustments on the cluster.

[S2central.net]

The speed sender generates a pulse train - adding resistors to it will not change that. ThesE pulses end up in the speedo module where a special chip drives the mechanical speedo and odometer - ime these always read slightly high in all cars for safety reasons. The chip in the speedo has a few supporting components that configure how it drives the gauge. Trouble is that it's not at all easy to unpick this from back of the cluster.

The speedo chip also generates the vss signal which goes to ecu, abs, rdl, radio/gala and cruise etc. Vss can bE logged on obd and along with a calibrated gps sensor would be possible to skew that result for better accuracy - but that doesn't help reading the speedo - if speedo comp changes are not possible then it would be interesting to have aftermarket gauges setup fo correct position as fond by gps test runs.

[DS2]

i kinda vaguely remember there were 3 pins behind the instrument cluster +-/ 5/ 10 % for the adjustment... may be remembering it from another car thou

[bikerjim]

I think thats for the trip computer for MPG etc

[Error404]

I never said they were 7A, just CQ. Can you post a pic of your speedo up please, I'm interested

You are right Andy, the 7A CQ speedo is slightly different too