digital Speedometer

Rune

Supporter
My plan was to use a mechanical speedometer and cable from the ZF 25-2 transaxle .
I wonder if there are senders to connect on the ZF ? and use a digital speedometer. I have to use a speedometer with km not mph, the authorities require this.
Someone out there with a good idea ?

Rune
 

Brian Stewart
Supporter
I have an electronic speedometer with a sender that screws into the speedo drive on the ZF. It is a Smiths (Caerbont) unit. Part #RIS-8PTEU Speed sensor 1:8, 1.5m Loom, 22 x 1.5mm euro.
 

Mike Pass

Supporter
I have the 100mm ETB Instruments electronic speedometer for quite a few years now. Correct size and appearance for GT40. uses a sensor and small magnets on the gearbox output/Cv joint. I have found them to be very helpful.

GT40 Replica


Cheers
Mike
 
I have a VDO speedometer/odometer being driven by a GPS transmitter. Initially this instrument received info from magnets installed on the half shaft. VDO's speedo head was capable of both types of signal input. I switched to get away from a wired system between the engine bay and the cockpit. The GPS sender mounts under the dash and requires a three wire hookup under the dash. Calibration took less than a minute and was accomplished without starting or driving the car. Highly recommend the GPS driven system.
 

Ian Anderson

Lifetime Supporter
I have the 100mm ETB Instruments electronic speedometer for quite a few years now. Correct size and appearance for GT40. uses a sensor and small magnets on the gearbox output/Cv joint. I have found them to be very helpful.

GT40 Replica


Cheers
Mike

Same in my car, excellent for over 10 years now!

Ian
 
Hi Mike,

I have the same ETB speedometer and sensor, just looking at mounting my sensor, any advice you can offer?? Are they easy to calibrate?

Cheers
 

Ian Anderson

Lifetime Supporter
Mount the magnets with arildite or similar. Suggest on the cv Adaptor as opposed to CV as if you knacker a CV you need to get new magnets.

Don't ask how I know

Ian
 

Mike Pass

Supporter
There are a couple of sensors which can drive the speedo. I have the Hall Effect sensor. The speedo is straightforward to calibrate. i have attached the wiring info for both sensors. Basically as Ian says glue the small magnets to the gearbox output flange with epoxy and then mount the sensor on a sheet metal bracket so it is close to the rotating magnets. Then connect up the sensor wires and positive and negative supply to the unit as per the diagram.

Cheers
Mike
 

Attachments

  • ETB hall effect sensor wiring diag.pdf
    240.3 KB · Views: 368
  • 100mm ETB speedo mag sensor.pdf
    81.3 KB · Views: 373

Ron Earp

Admin
I used aa GPS type speedometer in the Lola. Worked great and they are available in KPH and with a vintage look.
 
Perfect, thank you Mike and Ian, that's my next job in the garage when back from holiday, engine start next month all being well...
 

Rune

Supporter
The GPS speedometer is ok if you live in a place with no tunnels, but in Norway we have lots of tunnels so the authorities does not allow this as the only speedometer.
 
Bune,


I picked up an old 200MPH smiths speedo the other month, that is mechanical. I was looking into how to run it as well, even though I will probably need a KM/H gauge like you for rego purposes. still its a nice item to have on the shelf. It even has a remote trip distance counter reset button, not sure where I would put that on the dash!


I googled "electrical to mechanical speedometer converter" and items like this come up
SpeedBox™ Mechanical Cable Drive Converter


shouldn't be to hard to make up a device that is controlled by a little audrino controller, that takes in pulses from a wheel sensor and then turns a motor and speedo drive cable at a calibrated speed accordingly. essentially that is all the speedhut device is.


Ryan
 
You could always make a drive adapter for cable off front wheel, Hillman Imp was done like that, hole drilled thru stub axle and pin in dust cap to drive cable with plastic tang. LF wheel to get clockwise speedo direction IIRC. GT40 type front hub would be easier.
 
Back
Top