GPS Speedometer (analogue)

[Alan c]

A few months back a few of you pointed me in the right direction when my speedo cable failed on my sierra based Marlin. I have been looking at these options (mini 90deg drive for cable and new cable, or alternate of Hall effect speedo).

During research I came accross analogue GPS speedos which look a simple easy fit solution - anybody used these, any feedback?

http://www.speedhut.com/gauge/GR4-GPS-01/1/GPS-Speedometer-Gauge-120mph

PS - I was out for a run last week and Marlin was running "lumpy" swung by a motor factors and picked up a coil and fitted there and then - problem was insatntly solved. Similar thing happened on my MGA a few months back, it would cut out when hot - moral of story be aware of ageing coils!!!

Alan

[stevejgreen]

Re: GPS Speedometer (analogue)

Most antennas require a conductive ground plane, often the vehicles metallic bodyshell. Check with the manufacturer as to a prefered antenna location.
Expensive but neat solution but if like here in Spain, you travel through tunnels 1km or more long, where there are speed cameras fitted, it might not be such a good idea if there is no one else around to compare your speed to.

[lil_red_roadster]

Re: GPS Speedometer (analogue)

GPS are OK but they tell you how fast you were going rather than how fast you are going...OK, the lag is negligible before someone shoots me down with rocket science, but also assumes you can get a GPS signal (beware tunnels).
Why not try a free GPS speedo app on a cradle-mounted smartphone - that way you can try before you buy.

As regards digital speedos...

http://www.digital-speedos.co.uk/smiths-80mm-mphkph-speedometer-b-438-p.asp

The options box shows a Type 9 adaptor (the T9 can have a digital sender fitted to it) plus magnetic sensors.

Jez

[Alan c]

Re: GPS Speedometer (analogue)

Thanks Jez/Steve

The product info mentions tunnels I decided its a small comprimise.

The GPS antena is apparently 4 times stronger than the ones in your TomTom type GPS and update rate is 4hertz so speed is effectively real time.

It states antena mounting is on dash or windscreen but will check the requirements - its these little things that can catch you out

[CompoSimmonite]

Re: GPS Speedometer (analogue)

I thought a working speedo was a MOT requirement. How do you then get around that if testing station is all metal building so blocks GPS signal and speedo doesn't work ? I had an electronic aftermarket speedo and all it required was a signal from a sensor on wheel or propshaft and power. This is how I'd go rather than relying on a GPS speedo as the main instrument.

[b_caswell]

Re: GPS Speedometer (analogue)

This is the IVA requirement but the MOT requirement can't be far behind.

Note 1: The speedometer must be of a type suitable for M1 vehicle use. The types manufactured for bicycles, racing only, those that rely on GPS or those that require switching as a separate function to that of operating the vehicle or those that have a separate power source from the vehicle or where they do not operate as an automatic function when the vehicle is driven are not permitted. Where the device is in question the presenter may provide evidence as to the suitability of the device for road use from the manufacturer of the device.

[andyf]

Re: GPS Speedometer (analogue)

I think I'm going to stick to getting my analogue speedo repaired. It's a shame because getting the calibration right when using a non-standard tyre size, axle and gearbox combination can be tricky, my first attempt was off significantly.

[cameronfurnival]

Re: GPS Speedometer (analogue)

The MOT has only tested speedometers since 2012 (on vehicles made since 1937) and the reasons for failure are broken glass and if it cant be illuminated. I dont think it even has to be accurate for the test (how would they test it?). This is the MOT testers manual page
speedoRule.GIF

[lil_red_roadster]

Re: GPS Speedometer (analogue)

Snap Cameron

This is the IVA requirement but the MOT requirement can't be far behind.

Note 1: The speedometer must be of a type suitable for M1 vehicle use. The types manufactured for bicycles, racing only, those that rely on GPS or those that require switching as a separate function to that of operating the vehicle or those that have a separate power source from the vehicle or where they do not operate as an automatic function when the vehicle is driven are not permitted. Where the device is in question the presenter may provide evidence as to the suitability of the device for road use from the manufacturer of the device.

2012 MOT Notes only state that
1) A speedo must be fitted
2) Check the condition
3) Check it can be illuminated

There is no check that it functions correctly, but you can fail on this if it is "incomplete, clearly inoperative or the dial glass is broken/missing"

Accuracy is not checked - yet..!

[Alan c]

Re: GPS Speedometer (analogue)

MOT would appear not to be a road block to my plan (clarifications much appreciated). I may have an extra chat with my local MOT guys who I am on chatting terms with as to potential future issues.

If I am honest I am going for this option as I dont have the desire to crawl around under car (vertigo makes it a miserable experience) fitting a Hall effect sensor or re- routing a new speedo cable with little gearbox.

Also this speedos little screen for mileage has multi functions including compass, clock, max speed, 0-60 timing etc. some are gimmicks but a couple are useful at times.

I think I am heading towards taking a punt with it.

[scott h]

Re: GPS Speedometer (analogue)

When I built my Berly I used an electric analogue speedo. It used magnets fitted to the propshaft detected by a sensor. It was easily calibrated and worked well. I hope to still use it when I get the car back on the road but the sensor is a wee bit corroded and it seems to be hard to find a spare. Does anyone know of a UK supplier of Isspro gauges, originally purchased from Europa.

[DaveTrials]

Re: GPS Speedometer (analogue)

I have a system on my Gemini using magnets on the diff flange. The company i got them from is ETB instruments and it may be comapatible. They are very helpful on the phone.

[b_caswell]

Re: GPS Speedometer (analogue)

If you declare your mileage on your insurance policy it would be interesting to see what they will have to say about the accuracy of the milometer. Hope they don't look at mine.

[Alan c]

Re: GPS Speedometer (analogue)

Ben
The odeometer is the one question I still have to ask of the GPS speedo manufacturer (in that can it be programmed with the current mileage). My thinking was even a replacement regular mechanical speedo would show zero miles and somehow you would have to add old mileage to any declaration - not sure how that works.

If it is programable that could be an issue as I believe the car design rules say that milage should be tamper proof (obviously it is not if I can program it). This is my one area of concern.

Alan

[jon_cox]

Re: GPS Speedometer (analogue)

When I built my Berly I used an electric analogue speedo. It used magnets fitted to the propshaft detected by a sensor. It was easily calibrated and worked well. I hope to still use it when I get the car back on the road but the sensor is a wee bit corroded and it seems to be hard to find a spare. Does anyone know of a UK supplier of Isspro gauges, originally purchased from Europa.

Hi Scott. A few years ago at Stoneleigh I purchased an ISSPRO speed sensor from a company called Technisol. They have the one you describe on their website.

http://technisolltd.co.uk/collections/gauges/products/r8906-sensor-kit