Digital Speedo Sensor

[Simon Parish]

Hi all

 

I am thinking of a little winter project - a digital speedo.

I'm deciding to play scrooge this Christmas and not to spend money on buying on. Instead im going to try and build one. Now I'm not that good at this mechanics lark, but have been looking into the building of an electronic speedo. The one pint I'm pondering at the moment is Can I take the current speedo cable out of the gearbox and fit a hall effect sensor that would then be able to give me the signal output I need to get the digital speedo working

 

All help and advice would be greatly received

 

Thanks Simon

[knights_templar]

I've seen an adaptor that fits into the type 9 gearbox cable mount. http://www.ebay.co.uk/itm/Electronic-Speedo-Sensor-Ford-Type-9-Type-E-Rocket/151157144873?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D286%26meid%3D3015980621203153517%26pid%3D100005%26prg%3D1048%26rk%3D2%26rkt%3D5%26sd%3D161141687915%26

 

but you will need

 

http://www.ebay.co.uk/itm/Electronic-Speedo-Adaptor-Ford-Type-9-Type-E-Rocket-/161141687915?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2584cb066b

 

and you could always block that output and fit a sensor to pick up pulses from eiter the diff/prop or dif/output shafts. http://www.etbinstruments.com/Sensors_ancillaries.htm

[Simon Parish]

Hi RichardL

 

That is similar to what I was thinking, was looking at the Arduino board to drive all of the dash and get the inputs. Would love to share your code.

 

Currently I have the original Sierra instruments, but will be looking over the winter months to go for a digital speedo and odometer and then maybe even put the fuel, rev counter and temp guages over to the digital as time and knowledge allows

[Guest peter2b2002]

i have a hall effect sensor that I fitted to the end of the speedo cable but changed it as the drive gear in the box gave up , if you would like the sensor pm me for details

peter2b

[Guest red7]

Why not use a cheap hard wired bike magnetic sensor and display unit and make a backlit larger display?

[brumster]

Excellent little project! I love playing with MCUs too, I did a little project to make a sequential gear position indicator on an Atmel MCU...

 

My next idea, if I ever get to start it, is to make my own OLED/LED dash display to provide all information to the driver, but realistically it'll be months(years) before I ever get to pick it up and properly work at it. I was always looking at the Stack displays with a simple two-row character LCD and thinking boy they are milking people for some very basic technology there. There are also lots of LCD-based, non-dynamic displays like the Race Technology and ETB Digidash systems but they look a bit naff and cheap to me. Then you get the serious kit like the DTA XDash, Bosch motorsport and the Cosworth (Pi Research) motorsport displays, which are what I would want - fully configurable and dynamic in what they display - but not at several grand .

 

Good on you - will watch with interest!

[brumster]

Oh absolutely, I understand. OLED/LED/LCD certainly a lot more effort to make look 'pro'. And I suspect you'd get visibility issues with LCD, to be honest. There are some OLED displays that have the graphics driver chipset built into them, complete with a command set for doing rudimentary graphics (I've got one here in my project box to rig up some time and have a play). Half the reason it's gone nowhere is for exactly the reason you cite

 

A thought for your project - how about factoring in a relay driver for a variable-speed intermittent wipe based on road speed? If you fancied another challenge

[Guest snowy2]

I have used miicro reed switches and a button magnet...they are very reliable and very cheap <50p a time. If presented "end on" they are quite sensitive.

[sj-bradley]

Nice idea.

 

One point that hasn't been mentioned though is about the odometer readings. Is there a legal requirement to have this (E.g. MOT etc.) and will your home built one be deemed acceptable ?

 

(Or will you just hide away a genuine speedo to ensure that the miles are correctly clocked up?

 

Just a thought.

 

Simon.