This may be a silly question, but..... I am putting a supercharger on my moke (big wheel model 13inch), and will be swapping the diff to a 3.44 that I have in a gearbox in the shed. What speedo drive should I be fitting? the one from the original moke gearbox or the old mini one with the 3.44 diff?
Thanks,
Steve

Try plugging your tyre/diff/gearbox info in here and seeing how it looks. Do you know the tpm (or tpk) of the speedos?
http://guess-works.com/Tech/ratio.htm

_________________

Yep...try swapping the old mini one with the 3.44 diff...the difference between 10s and 13s may be acceptable...

If it were me, I would leave it as it is till you see what it shows at speed on the road

_________________
"Show me the Mini!"

So the speedo drive goes with the diff? I was wondering if speedo drive stayed with wheel size?. Speedo will be a new smiths one , no idea what tpm is, lol

Mokes have larger diameter wheels..

The diff ratio, speedo need to be matched with the two drive gears in the end of the gearbox. TPM is turns per mile and TPK is turns per km for metric units
http://guess-works.com/Tech/speedo.htm

_________________

I am changing to 3.44 diff at suggestion of supercharger builder in uk so i wont be changing gears every second. The original speedo drive is from the original moke gearbox 4.27 ( something like that), speedo will be a brand new smiths unit in km/ph. Just not sure which speedo drive would suit best, may be a case of trial and error?

If you know the tyre size and TPM/TPK of the new speedo there is a worm and pinion gear calculator I linked in the first reply:
http://guess-works.com/Tech/ratio.htm

_________________

Tyres will be 185 60 13 but as for the tpk im not sure ?

All Australian minis and mokes use the same speedo drive gears in the gearbox, it's the speedo head that differs. The tpm/tpk should be on the speedo face near the centre, then use the Guessworks calculator to figure out what drive gears will get you closest.

_________________
*witty signature*

Sapphire Blue Deluxe spread across three parts cars, two sheds and a driveway...

I was planning on buying a brand new speedo, does that mean i should ask them to make it suit my wheel size?

So we actually have multiple speedo problems to consider...maybe we should all wait till the dust settles

_________________
"Show me the Mini!"

You could fit the Smiths electronic one, then program it until perfect. Not cheap but a good solution.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I do like that option i can see that you buy a speedo sensor to suit, would your fuel wire just plug straight to it or need something in between? Anyone used one?

James in Wollongong has just fitted one. Fuel gauge connects as normal.
Speed sensor screws onto gearbox where cable was.

PM sent.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Awesome, thanks. Will definately go down this route after saving a few more pennies!