Go out for a little blast while the Mrs is on call annnnnnnd
Ping noise and now I have no speedo...
Cable is still fitted on both ends so it looks like I’ve snapped it. Check the big book of cobra bits to find out what cable I need and I find out that in 5800 miles it’s had 6 cables..
So, the issue is the routing at the gearbox end, which I can’t change, so I have a few options:
1) Import a $100 custom cable for it to break in 1000 miles ish.
2) Take the feed from a VSS sensor on the diff, like a E36 would, run it through a $300 converter and potentially still have an issue with the 90 degree gearbox behind the gauge
3) Buy a $360 GPS to mechanical converter (not strictly legal in the uk) and potentially still have an issue with the 90 degree gearbox behind the gauge
4) Spend £300 on a new electronic gauge and a gps feed unit
Leaning to option 4 atm.
Ordered a Smiths 100mm electronic Cobra style gauge today along with a Veethree gps sender.
New (to me) Smiths reverse sweep Cobra speedo is here.
I’ve rigged it up to work from a 12v plug supply as I have a little project I want to try with it.
As you can see it’s on 1547 miles. My Cobra is on 5900ish.
I want the mileage on the new speedo to match. Smiths in all sensibleness make them neigh on impossible to manipulate the mileage (for good reason).
So I need to think laterally. Each mile requires 16000 pulses to the speedo. If I set it to a feed at 761hz using an Adrino I’ve programmed it should set/run the speedo to 170mph... the stepper motor will have a fit if I set it to over 180mph, so 170 has a bit of safety built in.
I need to add 4350ish miles to it, so it’ll have to run for 25 and a bit hours.
In that time it’ll deliver 69,600,000 pulses and bobs your uncle the mileage will be correct on the new gauge.
Should be fun.
Its only bloody working!
Speedo also overreads by 1mph at 170!
Great success.
