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Fixed price repairs are based on the assumption that unit/s received
 are
‘original & complete’... a surcharge may be applied to cover
missing  parts etc...  If in doubt send in the unit for inspection
Good  luck with your project’...  Enjoy your classic motoring...
If  you  found this web site via a ‘search engine’ please
 check that you are looking @ the
latest version... click here
Mileage correction
Clocks
Other services
Post & packing
Contact details
Speedos
Rev counters
Jaguar XK 120 ( 1948 / 54 )
182.2M
Parts Order E-Mail Link
Payment options
Payment options
Payment options
Payment options
JDO Instruments

Classic Car Instrument Repairs ( Est 1963 )
Fixed price repairs for most British & European Classic Car Instruments
48hr service  available... Why pay more & wait longer ! No UK vat
Tele:   01535 603570 / Mobile: 07872 071512
Please check the  FAQ’s page  BEFORE ringing / texting / emailing
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If you are still ‘building your car’
The Speedo calibration can still be established providing you know the following information ...
Axle / Diff-ratio #  / Circumference of a fitted tyre ( correctly inflated ) / Number of turns the
‘Gear box Speedo output’ makes for
10 turns of the ‘ Prop-shaft output ’*
*( don’t forget to take any  ‘RIGHT ANGLE DRIVES’  into account e.g. Some drive units are not always 1:1 ! )

# To establish the ‘Axle / Diff-Ratio’ ... Lock one wheel / hub & turn the other wheel / hub 20 turns
( 10 turns for LSD... without locking a wheel / hub ) take up the slack first... ( approx ½ turn )
Count the ‘Prop-Shaft’ turns & divide by 10 to give the ‘Axle / Diff-Ratio’ ...
e.g. 37 turns = 3.7:1 & 42.5 turns would be 4.25:1 etc   

( if any of the above is not clear please ring / email for help / advice )
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Calculation page
Calculation page
Calculation page 1
Re-Calibration surcharge
Re-Calibration surcharge
Re calibration surcharge