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LCD dash update?
street - 18/10/03 at 01:04 PM

I seem to recall a discussion about using an Astra GTE digital dash in conjunction with a type 9 box, and one of the members was toying with the idea of using an Orion speedo cable with the trip computer to give the speed reading. Did you have any success?
To answer one of the questions on that post, the Orions transducer is of the 16 magnet veriety, as is the the GTE's (although some came with an 8 magnet transducer, you are unlikely to find one as they were for export only, and were fitted with a different transducer to compensate for the different size wheels that the export models had). Remember you can still run a standard Orion/Escort speedo off the speedo cable so you can compare the speed readings and calibrate the LCD clocks if neccesary.
Hope thats of some use, does anyone have any other information or have had the LCD speedo working using this method?

Street


Stu16v - 18/10/03 at 06:17 PM

Street, I have one fitted successfully in my car. Using the transducer from the donor car was a dead end due to the gearing differences between a T9 box speedo drive and the drive from the original vehicle.
As I have access to an original Astra GTE I was able to 'measure' how many pulses were sent to the dash for one wheel revolution. All I then had to do was strip a donor transducer to utilise the hall effect sensor, glue the relevant amount of magnets to something that rotates in the final drive system, and affix the modified sensor close to the magnets.
I found out that for one complete revolution of the Astra wheel, it sent 32 pulses to the dash. One pulse is created by the hall effect sensor 'seeing' a north and a south pole on a magnet. My first idea was to stick magnets on the driveshaft, but that would of meant I would need 64, and even with small magnets, there probably wouldnt be room......
But as the prop spins faster than the driveshafts, this means that you can have proportionally less magnets, i.e divide 64 by the final drive ratio. 64 divided by 3.6 equals 17.7. You do need an equal number (remember the glued on magnets need to be north/south/north/south etc), so I went for 18.
At SVA the car was travelling at 66 mph @ an indicated 70 mph, so happy with that!

The other guages within the dash can also be a little difficult to sort, depending on what engine you are using. But nothing is insurmountable.


HTH Stu.


street - 19/10/03 at 10:14 AM

Thanks for that Stu, a great help indeed. Shame about the Ford transducer not working, would have been really neat but it did seem a little too easy! Time to start playing with magnets and sensors again but its encouraging to hear someone has got one working succesfully.Thanks again

Street