Correct speedo drive for a VDP1300

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Andrew1967
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Correct speedo drive for a VDP1300

Post by Andrew1967 »

Can anyone advise what speedo drive we need for Dad's VDP1300 please ?

Standard ADO16 4 synchro box with 62/17 or 3.65:1 diff. Running standard 12" wheels with probably 145's or 155's.

The speedo currently in it (remembering it was an auto originally) has a TPI of 1280.

Had a look on Guessworks and had to make the details fit (so wrong vehicle (Mk3/4 Mini/Metro and wrong speedo but correct diff, TPI, 135x12 tyres ) .... comes up with 6/16.

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timmy201
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Re: Correct speedo drive for a VDP1300

Post by timmy201 »

To work it out you need the revs/mile - approx 927 for 155/80R12 tyres
The diff ratio - 3.65
Speedo gears - 6/16

927 x 3.65 x 6 / 16 = gives you 1269 tpm on the speedo - that’s within 1%

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Andrew1967
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Re: Correct speedo drive for a VDP1300

Post by Andrew1967 »

That's great, thanks for confirming that and advising 'how to' :D

Better check to see what drives we have now.

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Andrew1967
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Location: Usually in my garage on the east coast of Norfolk, UK

Re: Correct speedo drive for a VDP1300

Post by Andrew1967 »

Found a 6 tooth drive ... anyone got a 16 tooth pinion going spare ?

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