Thread: Speedometer

Originally Posted by B.S.F.Nut

For 6.00 / 6.50 / 7.00 x 16 tyres the speedo in Kms is 940.I'm using 7.00x16 cross plys ,and the 940 speedo is spot on. W.

Hello again from Brisbane.

Been a while since I made the original post on the topic (late last year) but I took up an opportunity last week to buy a new set of 7.50 X 16 tyres for my SWB S3. Not fitted yet since the truck is in bits under the house as part of a longer term restoration.

It presently has a set of well used 7.00 X 16 tyres on the rims but I believe it still has the original speedometer from when it probably wore 6.00 X 16 tyres as a newbie - these tyres were on it when I bought it and I have never driven it on the road. I will check the number on the speedo later to verify if that is correct. If it is the 6.00 X 16 model I am planning to replace it rather than do the mental calculation for the correct speed.

My reading of the previous threads on the topic list the relevant speedometer numbers as:

1408 7.50×16 (235/85 r16)
1504 6.50×16 (205/80 r16)
1536 6.00×16 (205/70 r16)

My question for now is that my local parts supplier has a Bearmach supplied NOS km speedometer on his shelf that can be secured at a "good" price. It is supposedly listed in their system as a speedometer for a S3/Defender (PRC 2607 BR 2329) and has "940" on the face. If I am reading the thread from BSF Nut correctly, then this particular speedometer head is not really appropriate for use with 7.50 X 16 tyres.

Is that correct?

Cheers,

My reading of the previous threads on the topic list the relevant speedometer numbers as:

1408 7.50×16 (235/85 r16)
1504 6.50×16 (205/80 r16)
1536 6.00×16 (205/70 r16)

My question for now is that my local parts supplier has a Bearmach supplied NOS km speedometer on his shelf that can be secured at a "good" price. It is supposedly listed in their system as a speedometer for a S3/Defender (PRC 2607 BR 2329) and has "940" on the face. If I am reading the thread from BSF Nut correctly, then this particular speedometer head is not really appropriate for use with 7.50 X 16 tyres.

Is that correct?

Cheers,[/QUOTE]

The above numbers are for a speedo in miles.
880 for 7.50x 16 in Km
940 for 6.00/700x16 in Km


.W.

Hello from Brisbane.

Thanks for clarifying that - I had guessed that the newer numbers were for later versions of the speedometer.

I suppose the real source of my confusion lay in reconciling the serial number of the speedometer (PRC 2607 BR 2329) and the revolution code on the face. Google that part number in and the returning advice is invariably "Series 3 109" and/or "Land Rover with 750 X 16" tyres". On the other hand the face code seems to contradict that.

I will go with your advice.

Cheers,

Hello again from Brisbane.

Pulled the cover off the truck under the house and had a look at the speedo - genuinely hard to read in poor light and the tight angle where it is written, but it appears to have the following number on the dial (km speedo to 140kph, with mph on an inner scale) - SNT6209 0145(?) and then 940.

From the earlier posts - especially noting the 940 - it would seem that this is probably the original 1975 installed speedo from when it likely wore 6.00 X 16" rubberware.

Cheers,

P.S. probably an expensive discovery apart from needing a 109" speedo - I decided to start the old beast for the first time in months and appear to have connected the battery around the wrong way without thinking - smoke signals from the back of the alternator. Started OK and the alternator light was going off under revs, but nature usually sides and all that........

Originally Posted by B.S.F.Nut

The above numbers are for a speedo in miles.
880 for 7.50x 16 in Km
940 for 6.00/700x16 in Km


.W.

Hello again.

Still looking for a replacement speedo for my 88" with 750 x 16" tyres.

Another vendor supposedly has one (NOS) for the model (0-140kph), but on inquiry about the face code (880 vs 940) has "860". Is this off another model with even larger tyres (or maybe poor eyesight)?

Accept that "940" is a no go, which both my truck and the new unit I was originally looking at have, but still a bit confused on all of this. All the usual UK suspects (Craddock, Paddock, Island, LR Direct etc) simply go off the serial number PRC2607 as being the correct metric speedo for 750 x 16" tyres.

Is that enough - order PRC2607 and Bob's your uncle? The last thing I want to do is pull something out of a box and find the dreaded "940" gracing its dial.

Cheers,

There are speedos with big numbers , big numbers with a smaller dial on the inside in miles/km,speedos with trip meters etc. and they all have got different part numbers.
880/940 etc. is the number of revs the speedo cable does per mile/km to show the correct speed and distance travelled for your particular vehicle. I can only tell you what works for me.880 speedos are far more common than 940s. It took me a couple of years till I found one at a Land Rover wreckers..W.

G'day All,

I've been following this thread with some interest. I have three speedo's to deal with when my resto gets to that stage. The original one ( at least the one in it when I got her) is a 940. There was a spare with the vehicle and there was one in the donor firewall - both 880's.

Now the tyres on Bella are 265/75R15, so what would be the best speedo to use if I keep the tyres and rims that I have? I've had a dabble at doing the convertions but I'm running into trouble going from metric to imperial.

Regards,

Marty.

Originally Posted by '76swb

G'day All,

I've been following this thread with some interest. I have three speedo's to deal with when my resto gets to that stage. The original one ( at least the one in it when I got her) is a 940. There was a spare with the vehicle and there was one in the donor firewall - both 880's.

Now the tyres on Bella are 265/75R15, so what would be the best speedo to use if I keep the tyres and rims that I have? I've had a dabble at doing the convertions but I'm running into trouble going from metric to imperial.

Regards,

Marty.

The 880 is your choice for most accuracy.

Tyre Size Calculator @ ExplorOz Articles

Use this calculator to work it out.

Cheers, Mick.