GPS Speedometer

[My72Sprint]

Reached out to Caerbont Automotive Instruments about Smiths speedometers availability.
https://www.smiths-instruments.co.uk/lotus
Received back:
SN6207-10 speedometer (mechanical, 980 turns per mile) - £211.11
SN6207-10CB speedometer (electronic, programmable) - £185.00
EMP34-1KIT inductive sender (M8 x 35mm) - £57.20
GPS01KIT GPS sender - £111.27

GPS for Smiths was new to me.
I’m going with electronic, programmable & GPS. Accurately unaffected by tire size & 5 speed conversion etc.
Tim

[gav]

Tim

That’s interesting - I have the electronic programmable speedo and when I enquired about the GPS sender they said that whilst the two are compatible, they cant be switched between modes, they have to be reset each time.

Gavin

[My72Sprint]

I not sure what "switched between modes" means from your post.
If I'm fixed with GPS only unable to use inductive sender no problem

My understanding electronic is programmable during manufacturer only.
They are working on user programable setting for odometer etc.

Tim

[gav]

Hi Tim

I meant that you could have inductive or GPS but if you wanted to switch from one to the other, that could be done but the unit would need to be recalibrated each time. That said, once the calibration number is established it is simply a case of re setting the reference number each time.
I was looking for a switch on the dash that could change from GPS to inductive and back at will and this is what they said I couldn’t do.
I think I’m going to find a calibrated mile and set the inductive and leave it there.

Hope that makes sense

Thanks
Gavin

[My72Sprint]

Got it now..
To your point they should allow GPS or inductive selection @ install.
Odometer total values should also be user changable.

They didn't have an avaliabliity date for upgraded software.
Tim

[wolfchen]

I have tried to fit various GPS speedo units to my motorcycle and found a distressingly high failure rate on the cheap circuits used, almost always the vibration of road use destroys the circuit board when I most need it, Also GPS signal strength can be problem , I like an electronic rally style that drive of front wheel had better luck with these

[gav]

While I have been sorting out the calibration of my speedo, I made a little bracket using the tonneau cover clips and am using a portable GPS unit. It works quite well there and hasn't rattled apart yet but that might be famous last words-

[My72Sprint]

Received Smiths speedometer with GPS from Caerbont Automotive.

Elan is under restoration ...
I temp wired / plugged speedometer/GPS into a cigarette lighter port another vehicle.
Drove to a nearby radar speed check location and speedometer matched radar reported values.
Speedometer 40 MPH = 40mph radar display.

Tim

[1owner69Elan]

I found an alternative unit through Speedhut, a maker of gauges for hot rods. It's called Speedbox.
https://www.speedhut.com/ecommerce/prod ... ical-Cable)

You can buy the unit with a cable but they're fixed length and will probably not fit our Speedometers. It also
determines where the unit resides in the car and I wanted to determine that myself. So I purchased this one
and had a custom length cable made. I brought the speedo and unit to a speedo shop and specified 'x' length.

I finished the install yesterday and went for a test drive. Although Speedhut says this is for US Domestic
speedometers, It worked perfectly and is dead accurate, per my speedometer app on my phone.

I'm very pleased and I think this is a very nice alternative.

Reviving this thread on GPS speedometers as my Classic Speed GPS box is no longer working. Since the Classic Speed is no longer in production not sure it is worthwhile (or even possible) to get it fixed.

The SpeedHut Speedbox alternative looks attractive but concerned about what cable is needed. Greg Z, can you supply any information on the cable that you had fabricated (quill size, cable ends) to be compatible with the Smiths mechanical gauge?

[h20hamelan]

have you looked at

https://www.dakotadigital.com/index.cfm ... &mode=prod

[1owner69Elan]

have you looked at

https://www.dakotadigital.com/index.cfm ... &mode=prod

Looks like this unit is for modern drivetrains with electronic output.

Looking for a GPS driven unit to original mechanical speedo.

The Dakota unit might be able to be driven by adding their GPS electronic output device. But, you then are adding an additional $200 and a lot of unneeded complexity and unneeded features.

[h20hamelan]

think it connects to you cell phone
could be wrong

[h20hamelan]

and while your at it
123 ignition

funny how our cars can run from a cell phone, ah well. progress I suppose

[gjz30075]

1owner, unfortunately those details I don't know. I simply brought *a* speedometer that has the same
input size as the one installed and the Speedbox to a local speedometer repair place with the required
speedometer cable length I needed and told them to make a cable to fit. As I recall, whatever size that
was required for the speedo end, also fit the Speedbox end. They, of course, also fit the necessary
nuts for tightening the sheath to their respective ends,ie, speedo and Speedbox. Nothing was out of the ordinary.

[TomR]

I use an electronic speedo (Smiths Cobra replica 100mm unit from Nisonger) with a programmable GPS driver box from Summit Racing for $99. No failure so far but i agree with previous posts that it is easy to lose the GPS signal. My cellphone GPS signal is better so it s a backup if I need it but of course the Smiths speedo and tach look way better on the dash:-)

One advantage to a fiberglass car is it is easy to hide the GPS antenna

Tom