wiring of a vdo speedo

[albanycobra]

VDO speedo's will read off anything....Use your g/box sensor for the ECU and
mount a Commodore ABS speed sensor (about $20 from a wrecker) right next to your tailshaft off the diff housing and it will read off the yoke bolts or get some of those cruise control signal weights and strap them to your tailshaft and mount the sensor near that. We mounted ours on the inner front hub and it counts off the old ABS ring.

There are lots of ways to mount a speed sensor and many types you can use.

Another idea is to use an after market Cruise control speed sensor that piggy backs manually straight off the g/box sensor, you just remove your existing speed sensor push the after market one in and fit a small drive shaft bewteen the original sensor and you have 2 seperate speed sensors driving off the gearbox. I used this type of set-up in my clubman.



Picture is for display only and not exactly what I used but you can get an idea of what I'm talking about.

[Ron61]

I don't know anything about your Cobra and the transmission, but I ran all VDO gages when I had mine, and I just used 3 wired for the speedometer. I had a Hall Effect Sensor that went in where you would put the gear on a gear drive transmission and it had a power wire, a ground wire and a sensor wire, all of which connected to terminals on the back of the speedometer. I had it for about 13 years and never a problem, even when I would change tire sizes or something, all I had to do was push the button until is said automatic, drive the car a mile and stop and push the button again and it would automatically set the speedometer for the change. I know it read right as I would then take it over to the CHP and ask them to go with me and we went to a deserted stretch of highway and they would use the radar to check my speed at 60,70,80, and 90. Always right on.

Ron

[Chris Brown]

Thanks sideshow I was thinking down that line but wasn't sure.

Thanks Dave if I don't have any luck with adding a extra positive I will call.

Thanks Ron I have had it wired like that for the past 4 years but its only now I have traced why it wont rev out.

Thanks again I am going to have another play I will let you know how it goes
Cheers Chris