Wildly inaccurate speedo

[charlie_morris_minor]

i have a pdf manual on stripping a speedo which i can let any one have, just PM me your email address

[Dominic]

As already said, you could get your speedo re calibrated. JDO is the best I have found: http://www.jdo1.com/index.html

I can second this - he charges about £30 + postage to repair and recalibrate if I remember rightly. He did a very good job on mine a few years ago.

[mike.perry]

It depends on what size tyres are fitted to the 13 in wheels. 175/80/13 tyres have the same circumference as 155/80/14 tyres

[JOWETTJAVELIN]

If it is over-reading at every speed you can remove the needle and re-set it and then try it against one of those electronic road signs which flash your speed. I did this with mine and got it almost bang-on, like within 1 mile an hour.

[Matt]

Yes there are different drive pinions on ford gearboxes.

All ford speedos run at 1000 TPM, and the pinions are changed dependant on diff ratio and tyre size.

There are lots of different pinions out there and they can be identified by differing colours. I know that the speedo drive pinion from MT75 gearboxes (sierras, transits etc) will fit, and I think the pinion from pretty much any RWD ford with a speedo cable will fit in to the type 9. This gives a wide range of avaliable ratios, and with the right pinion (trial and error i'm afraid) shoudl get you close to the right speedo reading.

The pinions are identified by colour.